8011427: java.util.concurrent collection Spliterator implementations
Reviewed-by: martin
Contributed-by: Doug Lea <dl@cs.oswego.edu>
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
*/
package java.util.concurrent;
import java.io.Serializable;
import java.io.ObjectStreamField;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.AbstractMap;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.ConcurrentModificationException;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.Spliterator;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.ReentrantLock;
import java.util.concurrent.locks.StampedLock;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import java.util.function.BinaryOperator;
import java.util.function.Consumer;
import java.util.function.DoubleBinaryOperator;
import java.util.function.Function;
import java.util.function.IntBinaryOperator;
import java.util.function.LongBinaryOperator;
import java.util.function.ToDoubleBiFunction;
import java.util.function.ToDoubleFunction;
import java.util.function.ToIntBiFunction;
import java.util.function.ToIntFunction;
import java.util.function.ToLongBiFunction;
import java.util.function.ToLongFunction;
import java.util.stream.Stream;
/**
* A hash table supporting full concurrency of retrievals and
* high expected concurrency for updates. This class obeys the
* same functional specification as {@link java.util.Hashtable}, and
* includes versions of methods corresponding to each method of
* {@code Hashtable}. However, even though all operations are
* thread-safe, retrieval operations do <em>not</em> entail locking,
* and there is <em>not</em> any support for locking the entire table
* in a way that prevents all access. This class is fully
* interoperable with {@code Hashtable} in programs that rely on its
* thread safety but not on its synchronization details.
*
* <p>Retrieval operations (including {@code get}) generally do not
* block, so may overlap with update operations (including {@code put}
* and {@code remove}). Retrievals reflect the results of the most
* recently <em>completed</em> update operations holding upon their
* onset. (More formally, an update operation for a given key bears a
* <em>happens-before</em> relation with any (non-null) retrieval for
* that key reporting the updated value.) For aggregate operations
* such as {@code putAll} and {@code clear}, concurrent retrievals may
* reflect insertion or removal of only some entries. Similarly,
* Iterators and Enumerations return elements reflecting the state of
* the hash table at some point at or since the creation of the
* iterator/enumeration. They do <em>not</em> throw {@link
* ConcurrentModificationException}. However, iterators are designed
* to be used by only one thread at a time. Bear in mind that the
* results of aggregate status methods including {@code size}, {@code
* isEmpty}, and {@code containsValue} are typically useful only when
* a map is not undergoing concurrent updates in other threads.
* Otherwise the results of these methods reflect transient states
* that may be adequate for monitoring or estimation purposes, but not
* for program control.
*
* <p>The table is dynamically expanded when there are too many
* collisions (i.e., keys that have distinct hash codes but fall into
* the same slot modulo the table size), with the expected average
* effect of maintaining roughly two bins per mapping (corresponding
* to a 0.75 load factor threshold for resizing). There may be much
* variance around this average as mappings are added and removed, but
* overall, this maintains a commonly accepted time/space tradeoff for
* hash tables. However, resizing this or any other kind of hash
* table may be a relatively slow operation. When possible, it is a
* good idea to provide a size estimate as an optional {@code
* initialCapacity} constructor argument. An additional optional
* {@code loadFactor} constructor argument provides a further means of
* customizing initial table capacity by specifying the table density
* to be used in calculating the amount of space to allocate for the
* given number of elements. Also, for compatibility with previous
* versions of this class, constructors may optionally specify an
* expected {@code concurrencyLevel} as an additional hint for
* internal sizing. Note that using many keys with exactly the same
* {@code hashCode()} is a sure way to slow down performance of any
* hash table. To ameliorate impact, when keys are {@link Comparable},
* this class may use comparison order among keys to help break ties.
*
* <p>A {@link Set} projection of a ConcurrentHashMap may be created
* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
* (using {@link #keySet(Object)} when only keys are of interest, and the
* mapped values are (perhaps transiently) not used or all take the
* same mapping value.
*
* <p>A ConcurrentHashMap can be used as scalable frequency map (a
* form of histogram or multiset) by using {@link
* java.util.concurrent.atomic.LongAdder} values and initializing via
* {@link #computeIfAbsent computeIfAbsent}. For example, to add a count
* to a {@code ConcurrentHashMap<String,LongAdder> freqs}, you can use
* {@code freqs.computeIfAbsent(k -> new LongAdder()).increment();}
*
* <p>This class and its views and iterators implement all of the
* <em>optional</em> methods of the {@link Map} and {@link Iterator}
* interfaces.
*
* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
* does <em>not</em> allow {@code null} to be used as a key or value.
*
* <p>ConcurrentHashMaps support a set of sequential and parallel bulk
* operations that, unlike most {@link Stream} methods, are designed
* to be safely, and often sensibly, applied even with maps that are
* being concurrently updated by other threads; for example, when
* computing a snapshot summary of the values in a shared registry.
* There are three kinds of operation, each with four forms, accepting
* functions with Keys, Values, Entries, and (Key, Value) arguments
* and/or return values. Because the elements of a ConcurrentHashMap
* are not ordered in any particular way, and may be processed in
* different orders in different parallel executions, the correctness
* of supplied functions should not depend on any ordering, or on any
* other objects or values that may transiently change while
* computation is in progress; and except for forEach actions, should
* ideally be side-effect-free. Bulk operations on {@link java.util.Map.Entry}
* objects do not support method {@code setValue}.
*
* <ul>
* <li> forEach: Perform a given action on each element.
* A variant form applies a given transformation on each element
* before performing the action.</li>
*
* <li> search: Return the first available non-null result of
* applying a given function on each element; skipping further
* search when a result is found.</li>
*
* <li> reduce: Accumulate each element. The supplied reduction
* function cannot rely on ordering (more formally, it should be
* both associative and commutative). There are five variants:
*
* <ul>
*
* <li> Plain reductions. (There is not a form of this method for
* (key, value) function arguments since there is no corresponding
* return type.)</li>
*
* <li> Mapped reductions that accumulate the results of a given
* function applied to each element.</li>
*
* <li> Reductions to scalar doubles, longs, and ints, using a
* given basis value.</li>
*
* </ul>
* </li>
* </ul>
*
* <p>These bulk operations accept a {@code parallelismThreshold}
* argument. Methods proceed sequentially if the current map size is
* estimated to be less than the given threshold. Using a value of
* {@code Long.MAX_VALUE} suppresses all parallelism. Using a value
* of {@code 1} results in maximal parallelism by partitioning into
* enough subtasks to fully utilize the {@link
* ForkJoinPool#commonPool()} that is used for all parallel
* computations. Normally, you would initially choose one of these
* extreme values, and then measure performance of using in-between
* values that trade off overhead versus throughput.
*
* <p>The concurrency properties of bulk operations follow
* from those of ConcurrentHashMap: Any non-null result returned
* from {@code get(key)} and related access methods bears a
* happens-before relation with the associated insertion or
* update. The result of any bulk operation reflects the
* composition of these per-element relations (but is not
* necessarily atomic with respect to the map as a whole unless it
* is somehow known to be quiescent). Conversely, because keys
* and values in the map are never null, null serves as a reliable
* atomic indicator of the current lack of any result. To
* maintain this property, null serves as an implicit basis for
* all non-scalar reduction operations. For the double, long, and
* int versions, the basis should be one that, when combined with
* any other value, returns that other value (more formally, it
* should be the identity element for the reduction). Most common
* reductions have these properties; for example, computing a sum
* with basis 0 or a minimum with basis MAX_VALUE.
*
* <p>Search and transformation functions provided as arguments
* should similarly return null to indicate the lack of any result
* (in which case it is not used). In the case of mapped
* reductions, this also enables transformations to serve as
* filters, returning null (or, in the case of primitive
* specializations, the identity basis) if the element should not
* be combined. You can create compound transformations and
* filterings by composing them yourself under this "null means
* there is nothing there now" rule before using them in search or
* reduce operations.
*
* <p>Methods accepting and/or returning Entry arguments maintain
* key-value associations. They may be useful for example when
* finding the key for the greatest value. Note that "plain" Entry
* arguments can be supplied using {@code new
* AbstractMap.SimpleEntry(k,v)}.
*
* <p>Bulk operations may complete abruptly, throwing an
* exception encountered in the application of a supplied
* function. Bear in mind when handling such exceptions that other
* concurrently executing functions could also have thrown
* exceptions, or would have done so if the first exception had
* not occurred.
*
* <p>Speedups for parallel compared to sequential forms are common
* but not guaranteed. Parallel operations involving brief functions
* on small maps may execute more slowly than sequential forms if the
* underlying work to parallelize the computation is more expensive
* than the computation itself. Similarly, parallelization may not
* lead to much actual parallelism if all processors are busy
* performing unrelated tasks.
*
* <p>All arguments to all task methods must be non-null.
*
* <p>This class is a member of the
* <a href="{@docRoot}/../technotes/guides/collections/index.html">
* Java Collections Framework</a>.
*
* @since 1.5
* @author Doug Lea
* @param <K> the type of keys maintained by this map
* @param <V> the type of mapped values
*/
@SuppressWarnings({"unchecked", "rawtypes", "serial"})
public class ConcurrentHashMap<K,V> extends AbstractMap<K,V>
implements ConcurrentMap<K,V>, Serializable {
private static final long serialVersionUID = 7249069246763182397L;
/*
* Overview:
*
* The primary design goal of this hash table is to maintain
* concurrent readability (typically method get(), but also
* iterators and related methods) while minimizing update
* contention. Secondary goals are to keep space consumption about
* the same or better than java.util.HashMap, and to support high
* initial insertion rates on an empty table by many threads.
*
* Each key-value mapping is held in a Node. Because Node key
* fields can contain special values, they are defined using plain
* Object types (not type "K"). This leads to a lot of explicit
* casting (and the use of class-wide warning suppressions). It
* also allows some of the public methods to be factored into a
* smaller number of internal methods (although sadly not so for
* the five variants of put-related operations). The
* validation-based approach explained below leads to a lot of
* code sprawl because retry-control precludes factoring into
* smaller methods.
*
* The table is lazily initialized to a power-of-two size upon the
* first insertion. Each bin in the table normally contains a
* list of Nodes (most often, the list has only zero or one Node).
* Table accesses require volatile/atomic reads, writes, and
* CASes. Because there is no other way to arrange this without
* adding further indirections, we use intrinsics
* (sun.misc.Unsafe) operations.
*
* We use the top (sign) bit of Node hash fields for control
* purposes -- it is available anyway because of addressing
* constraints. Nodes with negative hash fields are forwarding
* nodes to either TreeBins or resized tables. The lower 31 bits
* of each normal Node's hash field contain a transformation of
* the key's hash code.
*
* Insertion (via put or its variants) of the first node in an
* empty bin is performed by just CASing it to the bin. This is
* by far the most common case for put operations under most
* key/hash distributions. Other update operations (insert,
* delete, and replace) require locks. We do not want to waste
* the space required to associate a distinct lock object with
* each bin, so instead use the first node of a bin list itself as
* a lock. Locking support for these locks relies on builtin
* "synchronized" monitors.
*
* Using the first node of a list as a lock does not by itself
* suffice though: When a node is locked, any update must first
* validate that it is still the first node after locking it, and
* retry if not. Because new nodes are always appended to lists,
* once a node is first in a bin, it remains first until deleted
* or the bin becomes invalidated (upon resizing).
*
* The main disadvantage of per-bin locks is that other update
* operations on other nodes in a bin list protected by the same
* lock can stall, for example when user equals() or mapping
* functions take a long time. However, statistically, under
* random hash codes, this is not a common problem. Ideally, the
* frequency of nodes in bins follows a Poisson distribution
* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
* parameter of about 0.5 on average, given the resizing threshold
* of 0.75, although with a large variance because of resizing
* granularity. Ignoring variance, the expected occurrences of
* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The
* first values are:
*
* 0: 0.60653066
* 1: 0.30326533
* 2: 0.07581633
* 3: 0.01263606
* 4: 0.00157952
* 5: 0.00015795
* 6: 0.00001316
* 7: 0.00000094
* 8: 0.00000006
* more: less than 1 in ten million
*
* Lock contention probability for two threads accessing distinct
* elements is roughly 1 / (8 * #elements) under random hashes.
*
* Actual hash code distributions encountered in practice
* sometimes deviate significantly from uniform randomness. This
* includes the case when N > (1<<30), so some keys MUST collide.
* Similarly for dumb or hostile usages in which multiple keys are
* designed to have identical hash codes. Also, although we guard
* against the worst effects of this (see method spread), sets of
* hashes may differ only in bits that do not impact their bin
* index for a given power-of-two mask. So we use a secondary
* strategy that applies when the number of nodes in a bin exceeds
* a threshold, and at least one of the keys implements
* Comparable. These TreeBins use a balanced tree to hold nodes
* (a specialized form of red-black trees), bounding search time
* to O(log N). Each search step in a TreeBin is at least twice as
* slow as in a regular list, but given that N cannot exceed
* (1<<64) (before running out of addresses) this bounds search
* steps, lock hold times, etc, to reasonable constants (roughly
* 100 nodes inspected per operation worst case) so long as keys
* are Comparable (which is very common -- String, Long, etc).
* TreeBin nodes (TreeNodes) also maintain the same "next"
* traversal pointers as regular nodes, so can be traversed in
* iterators in the same way.
*
* The table is resized when occupancy exceeds a percentage
* threshold (nominally, 0.75, but see below). Any thread
* noticing an overfull bin may assist in resizing after the
* initiating thread allocates and sets up the replacement
* array. However, rather than stalling, these other threads may
* proceed with insertions etc. The use of TreeBins shields us
* from the worst case effects of overfilling while resizes are in
* progress. Resizing proceeds by transferring bins, one by one,
* from the table to the next table. To enable concurrency, the
* next table must be (incrementally) prefilled with place-holders
* serving as reverse forwarders to the old table. Because we are
* using power-of-two expansion, the elements from each bin must
* either stay at same index, or move with a power of two
* offset. We eliminate unnecessary node creation by catching
* cases where old nodes can be reused because their next fields
* won't change. On average, only about one-sixth of them need
* cloning when a table doubles. The nodes they replace will be
* garbage collectable as soon as they are no longer referenced by
* any reader thread that may be in the midst of concurrently
* traversing table. Upon transfer, the old table bin contains
* only a special forwarding node (with hash field "MOVED") that
* contains the next table as its key. On encountering a
* forwarding node, access and update operations restart, using
* the new table.
*
* Each bin transfer requires its bin lock, which can stall
* waiting for locks while resizing. However, because other
* threads can join in and help resize rather than contend for
* locks, average aggregate waits become shorter as resizing
* progresses. The transfer operation must also ensure that all
* accessible bins in both the old and new table are usable by any
* traversal. This is arranged by proceeding from the last bin
* (table.length - 1) up towards the first. Upon seeing a
* forwarding node, traversals (see class Traverser) arrange to
* move to the new table without revisiting nodes. However, to
* ensure that no intervening nodes are skipped, bin splitting can
* only begin after the associated reverse-forwarders are in
* place.
*
* The traversal scheme also applies to partial traversals of
* ranges of bins (via an alternate Traverser constructor)
* to support partitioned aggregate operations. Also, read-only
* operations give up if ever forwarded to a null table, which
* provides support for shutdown-style clearing, which is also not
* currently implemented.
*
* Lazy table initialization minimizes footprint until first use,
* and also avoids resizings when the first operation is from a
* putAll, constructor with map argument, or deserialization.
* These cases attempt to override the initial capacity settings,
* but harmlessly fail to take effect in cases of races.
*
* The element count is maintained using a specialization of
* LongAdder. We need to incorporate a specialization rather than
* just use a LongAdder in order to access implicit
* contention-sensing that leads to creation of multiple
* Cells. The counter mechanics avoid contention on
* updates but can encounter cache thrashing if read too
* frequently during concurrent access. To avoid reading so often,
* resizing under contention is attempted only upon adding to a
* bin already holding two or more nodes. Under uniform hash
* distributions, the probability of this occurring at threshold
* is around 13%, meaning that only about 1 in 8 puts check
* threshold (and after resizing, many fewer do so). The bulk
* putAll operation further reduces contention by only committing
* count updates upon these size checks.
*
* Maintaining API and serialization compatibility with previous
* versions of this class introduces several oddities. Mainly: We
* leave untouched but unused constructor arguments refering to
* concurrencyLevel. We accept a loadFactor constructor argument,
* but apply it only to initial table capacity (which is the only
* time that we can guarantee to honor it.) We also declare an
* unused "Segment" class that is instantiated in minimal form
* only when serializing.
*/
/* ---------------- Constants -------------- */
/**
* The largest possible table capacity. This value must be
* exactly 1<<30 to stay within Java array allocation and indexing
* bounds for power of two table sizes, and is further required
* because the top two bits of 32bit hash fields are used for
* control purposes.
*/
private static final int MAXIMUM_CAPACITY = 1 << 30;
/**
* The default initial table capacity. Must be a power of 2
* (i.e., at least 1) and at most MAXIMUM_CAPACITY.
*/
private static final int DEFAULT_CAPACITY = 16;
/**
* The largest possible (non-power of two) array size.
* Needed by toArray and related methods.
*/
static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
/**
* The default concurrency level for this table. Unused but
* defined for compatibility with previous versions of this class.
*/
private static final int DEFAULT_CONCURRENCY_LEVEL = 16;
/**
* The load factor for this table. Overrides of this value in
* constructors affect only the initial table capacity. The
* actual floating point value isn't normally used -- it is
* simpler to use expressions such as {@code n - (n >>> 2)} for
* the associated resizing threshold.
*/
private static final float LOAD_FACTOR = 0.75f;
/**
* The bin count threshold for using a tree rather than list for a
* bin. The value reflects the approximate break-even point for
* using tree-based operations.
*/
private static final int TREE_THRESHOLD = 8;
/**
* Minimum number of rebinnings per transfer step. Ranges are
* subdivided to allow multiple resizer threads. This value
* serves as a lower bound to avoid resizers encountering
* excessive memory contention. The value should be at least
* DEFAULT_CAPACITY.
*/
private static final int MIN_TRANSFER_STRIDE = 16;
/*
* Encodings for Node hash fields. See above for explanation.
*/
static final int MOVED = 0x80000000; // hash field for forwarding nodes
static final int HASH_BITS = 0x7fffffff; // usable bits of normal node hash
/** Number of CPUS, to place bounds on some sizings */
static final int NCPU = Runtime.getRuntime().availableProcessors();
/** For serialization compatibility. */
private static final ObjectStreamField[] serialPersistentFields = {
new ObjectStreamField("segments", Segment[].class),
new ObjectStreamField("segmentMask", Integer.TYPE),
new ObjectStreamField("segmentShift", Integer.TYPE)
};
/**
* A padded cell for distributing counts. Adapted from LongAdder
* and Striped64. See their internal docs for explanation.
*/
@sun.misc.Contended static final class Cell {
volatile long value;
Cell(long x) { value = x; }
}
/* ---------------- Fields -------------- */
/**
* The array of bins. Lazily initialized upon first insertion.
* Size is always a power of two. Accessed directly by iterators.
*/
transient volatile Node<K,V>[] table;
/**
* The next table to use; non-null only while resizing.
*/
private transient volatile Node<K,V>[] nextTable;
/**
* Base counter value, used mainly when there is no contention,
* but also as a fallback during table initialization
* races. Updated via CAS.
*/
private transient volatile long baseCount;
/**
* Table initialization and resizing control. When negative, the
* table is being initialized or resized: -1 for initialization,
* else -(1 + the number of active resizing threads). Otherwise,
* when table is null, holds the initial table size to use upon
* creation, or 0 for default. After initialization, holds the
* next element count value upon which to resize the table.
*/
private transient volatile int sizeCtl;
/**
* The next table index (plus one) to split while resizing.
*/
private transient volatile int transferIndex;
/**
* The least available table index to split while resizing.
*/
private transient volatile int transferOrigin;
/**
* Spinlock (locked via CAS) used when resizing and/or creating Cells.
*/
private transient volatile int cellsBusy;
/**
* Table of counter cells. When non-null, size is a power of 2.
*/
private transient volatile Cell[] counterCells;
// views
private transient KeySetView<K,V> keySet;
private transient ValuesView<K,V> values;
private transient EntrySetView<K,V> entrySet;
/* ---------------- Table element access -------------- */
/*
* Volatile access methods are used for table elements as well as
* elements of in-progress next table while resizing. Uses are
* null checked by callers, and implicitly bounds-checked, relying
* on the invariants that tab arrays have non-zero size, and all
* indices are masked with (tab.length - 1) which is never
* negative and always less than length. Note that, to be correct
* wrt arbitrary concurrency errors by users, bounds checks must
* operate on local variables, which accounts for some odd-looking
* inline assignments below.
*/
static final <K,V> Node<K,V> tabAt(Node<K,V>[] tab, int i) {
return (Node<K,V>)U.getObjectVolatile(tab, ((long)i << ASHIFT) + ABASE);
}
static final <K,V> boolean casTabAt(Node<K,V>[] tab, int i,
Node<K,V> c, Node<K,V> v) {
return U.compareAndSwapObject(tab, ((long)i << ASHIFT) + ABASE, c, v);
}
static final <K,V> void setTabAt(Node<K,V>[] tab, int i, Node<K,V> v) {
U.putObjectVolatile(tab, ((long)i << ASHIFT) + ABASE, v);
}
/* ---------------- Nodes -------------- */
/**
* Key-value entry. This class is never exported out as a
* user-mutable Map.Entry (i.e., one supporting setValue; see
* MapEntry below), but can be used for read-only traversals used
* in bulk tasks. Nodes with a hash field of MOVED are special,
* and do not contain user keys or values (and are never
* exported). Otherwise, keys and vals are never null.
*/
static class Node<K,V> implements Map.Entry<K,V> {
final int hash;
final Object key;
volatile V val;
Node<K,V> next;
Node(int hash, Object key, V val, Node<K,V> next) {
this.hash = hash;
this.key = key;
this.val = val;
this.next = next;
}
public final K getKey() { return (K)key; }
public final V getValue() { return val; }
public final int hashCode() { return key.hashCode() ^ val.hashCode(); }
public final String toString(){ return key + "=" + val; }
public final V setValue(V value) {
throw new UnsupportedOperationException();
}
public final boolean equals(Object o) {
Object k, v, u; Map.Entry<?,?> e;
return ((o instanceof Map.Entry) &&
(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
(v = e.getValue()) != null &&
(k == key || k.equals(key)) &&
(v == (u = val) || v.equals(u)));
}
}
/**
* Exported Entry for EntryIterator
*/
static final class MapEntry<K,V> implements Map.Entry<K,V> {
final K key; // non-null
V val; // non-null
final ConcurrentHashMap<K,V> map;
MapEntry(K key, V val, ConcurrentHashMap<K,V> map) {
this.key = key;
this.val = val;
this.map = map;
}
public K getKey() { return key; }
public V getValue() { return val; }
public int hashCode() { return key.hashCode() ^ val.hashCode(); }
public String toString() { return key + "=" + val; }
public boolean equals(Object o) {
Object k, v; Map.Entry<?,?> e;
return ((o instanceof Map.Entry) &&
(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
(v = e.getValue()) != null &&
(k == key || k.equals(key)) &&
(v == val || v.equals(val)));
}
/**
* Sets our entry's value and writes through to the map. The
* value to return is somewhat arbitrary here. Since we do not
* necessarily track asynchronous changes, the most recent
* "previous" value could be different from what we return (or
* could even have been removed, in which case the put will
* re-establish). We do not and cannot guarantee more.
*/
public V setValue(V value) {
if (value == null) throw new NullPointerException();
V v = val;
val = value;
map.put(key, value);
return v;
}
}
/* ---------------- TreeBins -------------- */
/**
* Nodes for use in TreeBins
*/
static final class TreeNode<K,V> extends Node<K,V> {
TreeNode<K,V> parent; // red-black tree links
TreeNode<K,V> left;
TreeNode<K,V> right;
TreeNode<K,V> prev; // needed to unlink next upon deletion
boolean red;
TreeNode(int hash, Object key, V val, Node<K,V> next,
TreeNode<K,V> parent) {
super(hash, key, val, next);
this.parent = parent;
}
}
/**
* Returns a Class for the given type of the form "class C
* implements Comparable<C>", if one exists, else null. See below
* for explanation.
*/
static Class<?> comparableClassFor(Class<?> c) {
Class<?> s, cmpc; Type[] ts, as; Type t; ParameterizedType p;
if (c == String.class) // bypass checks
return c;
if (c != null && (cmpc = Comparable.class).isAssignableFrom(c)) {
while (cmpc.isAssignableFrom(s = c.getSuperclass()))
c = s; // find topmost comparable class
if ((ts = c.getGenericInterfaces()) != null) {
for (int i = 0; i < ts.length; ++i) {
if (((t = ts[i]) instanceof ParameterizedType) &&
((p = (ParameterizedType)t).getRawType() == cmpc) &&
(as = p.getActualTypeArguments()) != null &&
as.length == 1 && as[0] == c) // type arg is c
return c;
}
}
}
return null;
}
/**
* A specialized form of red-black tree for use in bins
* whose size exceeds a threshold.
*
* TreeBins use a special form of comparison for search and
* related operations (which is the main reason we cannot use
* existing collections such as TreeMaps). TreeBins contain
* Comparable elements, but may contain others, as well as
* elements that are Comparable but not necessarily Comparable
* for the same T, so we cannot invoke compareTo among them. To
* handle this, the tree is ordered primarily by hash value, then
* by Comparable.compareTo order if applicable. On lookup at a
* node, if elements are not comparable or compare as 0 then both
* left and right children may need to be searched in the case of
* tied hash values. (This corresponds to the full list search
* that would be necessary if all elements were non-Comparable and
* had tied hashes.) The red-black balancing code is updated from
* pre-jdk-collections
* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
* based in turn on Cormen, Leiserson, and Rivest "Introduction to
* Algorithms" (CLR).
*
* TreeBins also maintain a separate locking discipline than
* regular bins. Because they are forwarded via special MOVED
* nodes at bin heads (which can never change once established),
* we cannot use those nodes as locks. Instead, TreeBin extends
* StampedLock to support a form of read-write lock. For update
* operations and table validation, the exclusive form of lock
* behaves in the same way as bin-head locks. However, lookups use
* shared read-lock mechanics to allow multiple readers in the
* absence of writers. Additionally, these lookups do not ever
* block: While the lock is not available, they proceed along the
* slow traversal path (via next-pointers) until the lock becomes
* available or the list is exhausted, whichever comes
* first. These cases are not fast, but maximize aggregate
* expected throughput.
*/
static final class TreeBin<K,V> extends StampedLock {
private static final long serialVersionUID = 2249069246763182397L;
transient TreeNode<K,V> root; // root of tree
transient TreeNode<K,V> first; // head of next-pointer list
/** From CLR */
private void rotateLeft(TreeNode<K,V> p) {
if (p != null) {
TreeNode<K,V> r = p.right, pp, rl;
if ((rl = p.right = r.left) != null)
rl.parent = p;
if ((pp = r.parent = p.parent) == null)
root = r;
else if (pp.left == p)
pp.left = r;
else
pp.right = r;
r.left = p;
p.parent = r;
}
}
/** From CLR */
private void rotateRight(TreeNode<K,V> p) {
if (p != null) {
TreeNode<K,V> l = p.left, pp, lr;
if ((lr = p.left = l.right) != null)
lr.parent = p;
if ((pp = l.parent = p.parent) == null)
root = l;
else if (pp.right == p)
pp.right = l;
else
pp.left = l;
l.right = p;
p.parent = l;
}
}
/**
* Returns the TreeNode (or null if not found) for the given key
* starting at given root.
*/
final TreeNode<K,V> getTreeNode(int h, Object k, TreeNode<K,V> p,
Class<?> cc) {
while (p != null) {
int dir, ph; Object pk; Class<?> pc;
if ((ph = p.hash) != h)
dir = (h < ph) ? -1 : 1;
else if ((pk = p.key) == k || k.equals(pk))
return p;
else if (cc == null || pk == null ||
((pc = pk.getClass()) != cc &&
comparableClassFor(pc) != cc) ||
(dir = ((Comparable<Object>)k).compareTo(pk)) == 0) {
TreeNode<K,V> r, pr; // check both sides
if ((pr = p.right) != null &&
(r = getTreeNode(h, k, pr, cc)) != null)
return r;
else // continue left
dir = -1;
}
p = (dir > 0) ? p.right : p.left;
}
return null;
}
/**
* Wrapper for getTreeNode used by CHM.get. Tries to obtain
* read-lock to call getTreeNode, but during failure to get
* lock, searches along next links.
*/
final V getValue(int h, Object k) {
Class<?> cc = comparableClassFor(k.getClass());
Node<K,V> r = null;
for (Node<K,V> e = first; e != null; e = e.next) {
long s;
if ((s = tryReadLock()) != 0L) {
try {
r = getTreeNode(h, k, root, cc);
} finally {
unlockRead(s);
}
break;
}
else if (e.hash == h && k.equals(e.key)) {
r = e;
break;
}
}
return r == null ? null : r.val;
}
/**
* Finds or adds a node.
* @return null if added
*/
final TreeNode<K,V> putTreeNode(int h, Object k, V v) {
Class<?> cc = comparableClassFor(k.getClass());
TreeNode<K,V> pp = root, p = null;
int dir = 0;
while (pp != null) { // find existing node or leaf to insert at
int ph; Object pk; Class<?> pc;
p = pp;
if ((ph = p.hash) != h)
dir = (h < ph) ? -1 : 1;
else if ((pk = p.key) == k || k.equals(pk))
return p;
else if (cc == null || pk == null ||
((pc = pk.getClass()) != cc &&
comparableClassFor(pc) != cc) ||
(dir = ((Comparable<Object>)k).compareTo(pk)) == 0) {
TreeNode<K,V> r, pr;
if ((pr = p.right) != null &&
(r = getTreeNode(h, k, pr, cc)) != null)
return r;
else // continue left
dir = -1;
}
pp = (dir > 0) ? p.right : p.left;
}
TreeNode<K,V> f = first;
TreeNode<K,V> x = first = new TreeNode<K,V>(h, k, v, f, p);
if (p == null)
root = x;
else { // attach and rebalance; adapted from CLR
if (f != null)
f.prev = x;
if (dir <= 0)
p.left = x;
else
p.right = x;
x.red = true;
for (TreeNode<K,V> xp, xpp, xppl, xppr;;) {
if ((xp = x.parent) == null) {
(root = x).red = false;
break;
}
else if (!xp.red || (xpp = xp.parent) == null) {
TreeNode<K,V> r = root;
if (r != null && r.red)
r.red = false;
break;
}
else if ((xppl = xpp.left) == xp) {
if ((xppr = xpp.right) != null && xppr.red) {
xppr.red = false;
xp.red = false;
xpp.red = true;
x = xpp;
}
else {
if (x == xp.right) {
rotateLeft(x = xp);
xpp = (xp = x.parent) == null ? null : xp.parent;
}
if (xp != null) {
xp.red = false;
if (xpp != null) {
xpp.red = true;
rotateRight(xpp);
}
}
}
}
else {
if (xppl != null && xppl.red) {
xppl.red = false;
xp.red = false;
xpp.red = true;
x = xpp;
}
else {
if (x == xp.left) {
rotateRight(x = xp);
xpp = (xp = x.parent) == null ? null : xp.parent;
}
if (xp != null) {
xp.red = false;
if (xpp != null) {
xpp.red = true;
rotateLeft(xpp);
}
}
}
}
}
}
assert checkInvariants();
return null;
}
/**
* Removes the given node, that must be present before this
* call. This is messier than typical red-black deletion code
* because we cannot swap the contents of an interior node
* with a leaf successor that is pinned by "next" pointers
* that are accessible independently of lock. So instead we
* swap the tree linkages.
*/
final void deleteTreeNode(TreeNode<K,V> p) {
TreeNode<K,V> next = (TreeNode<K,V>)p.next;
TreeNode<K,V> pred = p.prev; // unlink traversal pointers
if (pred == null)
first = next;
else
pred.next = next;
if (next != null)
next.prev = pred;
else if (pred == null) {
root = null;
return;
}
TreeNode<K,V> replacement;
TreeNode<K,V> pl = p.left;
TreeNode<K,V> pr = p.right;
if (pl != null && pr != null) {
TreeNode<K,V> s = pr, sl;
while ((sl = s.left) != null) // find successor
s = sl;
boolean c = s.red; s.red = p.red; p.red = c; // swap colors
TreeNode<K,V> sr = s.right;
TreeNode<K,V> pp = p.parent;
if (s == pr) { // p was s's direct parent
p.parent = s;
s.right = p;
}
else {
TreeNode<K,V> sp = s.parent;
if ((p.parent = sp) != null) {
if (s == sp.left)
sp.left = p;
else
sp.right = p;
}
if ((s.right = pr) != null)
pr.parent = s;
}
p.left = null;
if ((p.right = sr) != null)
sr.parent = p;
if ((s.left = pl) != null)
pl.parent = s;
if ((s.parent = pp) == null)
root = s;
else if (p == pp.left)
pp.left = s;
else
pp.right = s;
if (sr != null)
replacement = sr;
else
replacement = p;
}
else if (pl != null)
replacement = pl;
else if (pr != null)
replacement = pr;
else
replacement = p;
if (replacement != p) {
TreeNode<K,V> pp = replacement.parent = p.parent;
if (pp == null)
root = replacement;
else if (p == pp.left)
pp.left = replacement;
else
pp.right = replacement;
p.left = p.right = p.parent = null;
}
if (!p.red) { // rebalance, from CLR
for (TreeNode<K,V> x = replacement; x != null; ) {
TreeNode<K,V> xp, xpl, xpr;
if (x.red || (xp = x.parent) == null) {
x.red = false;
break;
}
else if ((xpl = xp.left) == x) {
if ((xpr = xp.right) != null && xpr.red) {
xpr.red = false;
xp.red = true;
rotateLeft(xp);
xpr = (xp = x.parent) == null ? null : xp.right;
}
if (xpr == null)
x = xp;
else {
TreeNode<K,V> sl = xpr.left, sr = xpr.right;
if ((sr == null || !sr.red) &&
(sl == null || !sl.red)) {
xpr.red = true;
x = xp;
}
else {
if (sr == null || !sr.red) {
if (sl != null)
sl.red = false;
xpr.red = true;
rotateRight(xpr);
xpr = (xp = x.parent) == null ?
null : xp.right;
}
if (xpr != null) {
xpr.red = (xp == null) ? false : xp.red;
if ((sr = xpr.right) != null)
sr.red = false;
}
if (xp != null) {
xp.red = false;
rotateLeft(xp);
}
x = root;
}
}
}
else { // symmetric
if (xpl != null && xpl.red) {
xpl.red = false;
xp.red = true;
rotateRight(xp);
xpl = (xp = x.parent) == null ? null : xp.left;
}
if (xpl == null)
x = xp;
else {
TreeNode<K,V> sl = xpl.left, sr = xpl.right;
if ((sl == null || !sl.red) &&
(sr == null || !sr.red)) {
xpl.red = true;
x = xp;
}
else {
if (sl == null || !sl.red) {
if (sr != null)
sr.red = false;
xpl.red = true;
rotateLeft(xpl);
xpl = (xp = x.parent) == null ?
null : xp.left;
}
if (xpl != null) {
xpl.red = (xp == null) ? false : xp.red;
if ((sl = xpl.left) != null)
sl.red = false;
}
if (xp != null) {
xp.red = false;
rotateRight(xp);
}
x = root;
}
}
}
}
}
if (p == replacement) { // detach pointers
TreeNode<K,V> pp;
if ((pp = p.parent) != null) {
if (p == pp.left)
pp.left = null;
else if (p == pp.right)
pp.right = null;
p.parent = null;
}
}
assert checkInvariants();
}
/**
* Checks linkage and balance invariants at root
*/
final boolean checkInvariants() {
TreeNode<K,V> r = root;
if (r == null)
return (first == null);
else
return (first != null) && checkTreeNode(r);
}
/**
* Recursive invariant check
*/
final boolean checkTreeNode(TreeNode<K,V> t) {
TreeNode<K,V> tp = t.parent, tl = t.left, tr = t.right,
tb = t.prev, tn = (TreeNode<K,V>)t.next;
if (tb != null && tb.next != t)
return false;
if (tn != null && tn.prev != t)
return false;
if (tp != null && t != tp.left && t != tp.right)
return false;
if (tl != null && (tl.parent != t || tl.hash > t.hash))
return false;
if (tr != null && (tr.parent != t || tr.hash < t.hash))
return false;
if (t.red && tl != null && tl.red && tr != null && tr.red)
return false;
if (tl != null && !checkTreeNode(tl))
return false;
if (tr != null && !checkTreeNode(tr))
return false;
return true;
}
}
/* ---------------- Collision reduction methods -------------- */
/**
* Spreads higher bits to lower, and also forces top bit to 0.
* Because the table uses power-of-two masking, sets of hashes
* that vary only in bits above the current mask will always
* collide. (Among known examples are sets of Float keys holding
* consecutive whole numbers in small tables.) To counter this,
* we apply a transform that spreads the impact of higher bits
* downward. There is a tradeoff between speed, utility, and
* quality of bit-spreading. Because many common sets of hashes
* are already reasonably distributed across bits (so don't benefit
* from spreading), and because we use trees to handle large sets
* of collisions in bins, we don't need excessively high quality.
*/
private static final int spread(int h) {
h ^= (h >>> 18) ^ (h >>> 12);
return (h ^ (h >>> 10)) & HASH_BITS;
}
/**
* Replaces a list bin with a tree bin if key is comparable. Call
* only when locked.
*/
private final void replaceWithTreeBin(Node<K,V>[] tab, int index, Object key) {
if (tab != null && comparableClassFor(key.getClass()) != null) {
TreeBin<K,V> t = new TreeBin<K,V>();
for (Node<K,V> e = tabAt(tab, index); e != null; e = e.next)
t.putTreeNode(e.hash, e.key, e.val);
setTabAt(tab, index, new Node<K,V>(MOVED, t, null, null));
}
}
/* ---------------- Internal access and update methods -------------- */
/** Implementation for get and containsKey */
private final V internalGet(Object k) {
int h = spread(k.hashCode());
V v = null;
Node<K,V>[] tab; Node<K,V> e;
if ((tab = table) != null &&
(e = tabAt(tab, (tab.length - 1) & h)) != null) {
for (;;) {
int eh; Object ek;
if ((eh = e.hash) < 0) {
if ((ek = e.key) instanceof TreeBin) { // search TreeBin
v = ((TreeBin<K,V>)ek).getValue(h, k);
break;
}
else if (!(ek instanceof Node[]) || // try new table
(e = tabAt(tab = (Node<K,V>[])ek,
(tab.length - 1) & h)) == null)
break;
}
else if (eh == h && ((ek = e.key) == k || k.equals(ek))) {
v = e.val;
break;
}
else if ((e = e.next) == null)
break;
}
}
return v;
}
/**
* Implementation for the four public remove/replace methods:
* Replaces node value with v, conditional upon match of cv if
* non-null. If resulting value is null, delete.
*/
private final V internalReplace(Object k, V v, Object cv) {
int h = spread(k.hashCode());
V oldVal = null;
for (Node<K,V>[] tab = table;;) {
Node<K,V> f; int i, fh; Object fk;
if (tab == null ||
(f = tabAt(tab, i = (tab.length - 1) & h)) == null)
break;
else if ((fh = f.hash) < 0) {
if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
boolean validated = false;
boolean deleted = false;
try {
if (tabAt(tab, i) == f) {
validated = true;
Class<?> cc = comparableClassFor(k.getClass());
TreeNode<K,V> p = t.getTreeNode(h, k, t.root, cc);
if (p != null) {
V pv = p.val;
if (cv == null || cv == pv || cv.equals(pv)) {
oldVal = pv;
if (v != null)
p.val = v;
else {
deleted = true;
t.deleteTreeNode(p);
}
}
}
}
} finally {
t.unlockWrite(stamp);
}
if (validated) {
if (deleted)
addCount(-1L, -1);
break;
}
}
else
tab = (Node<K,V>[])fk;
}
else {
boolean validated = false;
boolean deleted = false;
synchronized (f) {
if (tabAt(tab, i) == f) {
validated = true;
for (Node<K,V> e = f, pred = null;;) {
Object ek;
if (e.hash == h &&
((ek = e.key) == k || k.equals(ek))) {
V ev = e.val;
if (cv == null || cv == ev || cv.equals(ev)) {
oldVal = ev;
if (v != null)
e.val = v;
else {
deleted = true;
Node<K,V> en = e.next;
if (pred != null)
pred.next = en;
else
setTabAt(tab, i, en);
}
}
break;
}
pred = e;
if ((e = e.next) == null)
break;
}
}
}
if (validated) {
if (deleted)
addCount(-1L, -1);
break;
}
}
}
return oldVal;
}
/*
* Internal versions of insertion methods
* All have the same basic structure as the first (internalPut):
* 1. If table uninitialized, create
* 2. If bin empty, try to CAS new node
* 3. If bin stale, use new table
* 4. if bin converted to TreeBin, validate and relay to TreeBin methods
* 5. Lock and validate; if valid, scan and add or update
*
* The putAll method differs mainly in attempting to pre-allocate
* enough table space, and also more lazily performs count updates
* and checks.
*
* Most of the function-accepting methods can't be factored nicely
* because they require different functional forms, so instead
* sprawl out similar mechanics.
*/
/** Implementation for put and putIfAbsent */
private final V internalPut(K k, V v, boolean onlyIfAbsent) {
if (k == null || v == null) throw new NullPointerException();
int h = spread(k.hashCode());
int len = 0;
for (Node<K,V>[] tab = table;;) {
int i, fh; Node<K,V> f; Object fk;
if (tab == null)
tab = initTable();
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
if (casTabAt(tab, i, null, new Node<K,V>(h, k, v, null)))
break; // no lock when adding to empty bin
}
else if ((fh = f.hash) < 0) {
if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
V oldVal = null;
try {
if (tabAt(tab, i) == f) {
len = 2;
TreeNode<K,V> p = t.putTreeNode(h, k, v);
if (p != null) {
oldVal = p.val;
if (!onlyIfAbsent)
p.val = v;
}
}
} finally {
t.unlockWrite(stamp);
}
if (len != 0) {
if (oldVal != null)
return oldVal;
break;
}
}
else
tab = (Node<K,V>[])fk;
}
else {
V oldVal = null;
synchronized (f) {
if (tabAt(tab, i) == f) {
len = 1;
for (Node<K,V> e = f;; ++len) {
Object ek;
if (e.hash == h &&
((ek = e.key) == k || k.equals(ek))) {
oldVal = e.val;
if (!onlyIfAbsent)
e.val = v;
break;
}
Node<K,V> last = e;
if ((e = e.next) == null) {
last.next = new Node<K,V>(h, k, v, null);
if (len > TREE_THRESHOLD)
replaceWithTreeBin(tab, i, k);
break;
}
}
}
}
if (len != 0) {
if (oldVal != null)
return oldVal;
break;
}
}
}
addCount(1L, len);
return null;
}
/** Implementation for computeIfAbsent */
private final V internalComputeIfAbsent(K k, Function<? super K, ? extends V> mf) {
if (k == null || mf == null)
throw new NullPointerException();
int h = spread(k.hashCode());
V val = null;
int len = 0;
for (Node<K,V>[] tab = table;;) {
Node<K,V> f; int i; Object fk;
if (tab == null)
tab = initTable();
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
Node<K,V> node = new Node<K,V>(h, k, null, null);
synchronized (node) {
if (casTabAt(tab, i, null, node)) {
len = 1;
try {
if ((val = mf.apply(k)) != null)
node.val = val;
} finally {
if (val == null)
setTabAt(tab, i, null);
}
}
}
if (len != 0)
break;
}
else if (f.hash < 0) {
if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
boolean added = false;
try {
if (tabAt(tab, i) == f) {
len = 2;
Class<?> cc = comparableClassFor(k.getClass());
TreeNode<K,V> p = t.getTreeNode(h, k, t.root, cc);
if (p != null)
val = p.val;
else if ((val = mf.apply(k)) != null) {
added = true;
t.putTreeNode(h, k, val);
}
}
} finally {
t.unlockWrite(stamp);
}
if (len != 0) {
if (!added)
return val;
break;
}
}
else
tab = (Node<K,V>[])fk;
}
else {
boolean added = false;
synchronized (f) {
if (tabAt(tab, i) == f) {
len = 1;
for (Node<K,V> e = f;; ++len) {
Object ek; V ev;
if (e.hash == h &&
((ek = e.key) == k || k.equals(ek))) {
val = e.val;
break;
}
Node<K,V> last = e;
if ((e = e.next) == null) {
if ((val = mf.apply(k)) != null) {
added = true;
last.next = new Node<K,V>(h, k, val, null);
if (len > TREE_THRESHOLD)
replaceWithTreeBin(tab, i, k);
}
break;
}
}
}
}
if (len != 0) {
if (!added)
return val;
break;
}
}
}
if (val != null)
addCount(1L, len);
return val;
}
/** Implementation for compute */
private final V internalCompute(K k, boolean onlyIfPresent,
BiFunction<? super K, ? super V, ? extends V> mf) {
if (k == null || mf == null)
throw new NullPointerException();
int h = spread(k.hashCode());
V val = null;
int delta = 0;
int len = 0;
for (Node<K,V>[] tab = table;;) {
Node<K,V> f; int i, fh; Object fk;
if (tab == null)
tab = initTable();
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
if (onlyIfPresent)
break;
Node<K,V> node = new Node<K,V>(h, k, null, null);
synchronized (node) {
if (casTabAt(tab, i, null, node)) {
try {
len = 1;
if ((val = mf.apply(k, null)) != null) {
node.val = val;
delta = 1;
}
} finally {
if (delta == 0)
setTabAt(tab, i, null);
}
}
}
if (len != 0)
break;
}
else if ((fh = f.hash) < 0) {
if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
try {
if (tabAt(tab, i) == f) {
len = 2;
Class<?> cc = comparableClassFor(k.getClass());
TreeNode<K,V> p = t.getTreeNode(h, k, t.root, cc);
if (p != null || !onlyIfPresent) {
V pv = (p == null) ? null : p.val;
if ((val = mf.apply(k, pv)) != null) {
if (p != null)
p.val = val;
else {
delta = 1;
t.putTreeNode(h, k, val);
}
}
else if (p != null) {
delta = -1;
t.deleteTreeNode(p);
}
}
}
} finally {
t.unlockWrite(stamp);
}
if (len != 0)
break;
}
else
tab = (Node<K,V>[])fk;
}
else {
synchronized (f) {
if (tabAt(tab, i) == f) {
len = 1;
for (Node<K,V> e = f, pred = null;; ++len) {
Object ek;
if (e.hash == h &&
((ek = e.key) == k || k.equals(ek))) {
val = mf.apply(k, e.val);
if (val != null)
e.val = val;
else {
delta = -1;
Node<K,V> en = e.next;
if (pred != null)
pred.next = en;
else
setTabAt(tab, i, en);
}
break;
}
pred = e;
if ((e = e.next) == null) {
if (!onlyIfPresent &&
(val = mf.apply(k, null)) != null) {
pred.next = new Node<K,V>(h, k, val, null);
delta = 1;
if (len > TREE_THRESHOLD)
replaceWithTreeBin(tab, i, k);
}
break;
}
}
}
}
if (len != 0)
break;
}
}
if (delta != 0)
addCount((long)delta, len);
return val;
}
/** Implementation for merge */
private final V internalMerge(K k, V v,
BiFunction<? super V, ? super V, ? extends V> mf) {
if (k == null || v == null || mf == null)
throw new NullPointerException();
int h = spread(k.hashCode());
V val = null;
int delta = 0;
int len = 0;
for (Node<K,V>[] tab = table;;) {
int i; Node<K,V> f; Object fk;
if (tab == null)
tab = initTable();
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
if (casTabAt(tab, i, null, new Node<K,V>(h, k, v, null))) {
delta = 1;
val = v;
break;
}
}
else if (f.hash < 0) {
if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
try {
if (tabAt(tab, i) == f) {
len = 2;
Class<?> cc = comparableClassFor(k.getClass());
TreeNode<K,V> p = t.getTreeNode(h, k, t.root, cc);
val = (p == null) ? v : mf.apply(p.val, v);
if (val != null) {
if (p != null)
p.val = val;
else {
delta = 1;
t.putTreeNode(h, k, val);
}
}
else if (p != null) {
delta = -1;
t.deleteTreeNode(p);
}
}
} finally {
t.unlockWrite(stamp);
}
if (len != 0)
break;
}
else
tab = (Node<K,V>[])fk;
}
else {
synchronized (f) {
if (tabAt(tab, i) == f) {
len = 1;
for (Node<K,V> e = f, pred = null;; ++len) {
Object ek;
if (e.hash == h &&
((ek = e.key) == k || k.equals(ek))) {
val = mf.apply(e.val, v);
if (val != null)
e.val = val;
else {
delta = -1;
Node<K,V> en = e.next;
if (pred != null)
pred.next = en;
else
setTabAt(tab, i, en);
}
break;
}
pred = e;
if ((e = e.next) == null) {
delta = 1;
val = v;
pred.next = new Node<K,V>(h, k, val, null);
if (len > TREE_THRESHOLD)
replaceWithTreeBin(tab, i, k);
break;
}
}
}
}
if (len != 0)
break;
}
}
if (delta != 0)
addCount((long)delta, len);
return val;
}
/** Implementation for putAll */
private final void internalPutAll(Map<? extends K, ? extends V> m) {
tryPresize(m.size());
long delta = 0L; // number of uncommitted additions
boolean npe = false; // to throw exception on exit for nulls
try { // to clean up counts on other exceptions
for (Map.Entry<?, ? extends V> entry : m.entrySet()) {
Object k; V v;
if (entry == null || (k = entry.getKey()) == null ||
(v = entry.getValue()) == null) {
npe = true;
break;
}
int h = spread(k.hashCode());
for (Node<K,V>[] tab = table;;) {
int i; Node<K,V> f; int fh; Object fk;
if (tab == null)
tab = initTable();
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null){
if (casTabAt(tab, i, null, new Node<K,V>(h, k, v, null))) {
++delta;
break;
}
}
else if ((fh = f.hash) < 0) {
if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
boolean validated = false;
try {
if (tabAt(tab, i) == f) {
validated = true;
Class<?> cc = comparableClassFor(k.getClass());
TreeNode<K,V> p = t.getTreeNode(h, k,
t.root, cc);
if (p != null)
p.val = v;
else {
++delta;
t.putTreeNode(h, k, v);
}
}
} finally {
t.unlockWrite(stamp);
}
if (validated)
break;
}
else
tab = (Node<K,V>[])fk;
}
else {
int len = 0;
synchronized (f) {
if (tabAt(tab, i) == f) {
len = 1;
for (Node<K,V> e = f;; ++len) {
Object ek;
if (e.hash == h &&
((ek = e.key) == k || k.equals(ek))) {
e.val = v;
break;
}
Node<K,V> last = e;
if ((e = e.next) == null) {
++delta;
last.next = new Node<K,V>(h, k, v, null);
if (len > TREE_THRESHOLD)
replaceWithTreeBin(tab, i, k);
break;
}
}
}
}
if (len != 0) {
if (len > 1) {
addCount(delta, len);
delta = 0L;
}
break;
}
}
}
}
} finally {
if (delta != 0L)
addCount(delta, 2);
}
if (npe)
throw new NullPointerException();
}
/**
* Implementation for clear. Steps through each bin, removing all
* nodes.
*/
private final void internalClear() {
long delta = 0L; // negative number of deletions
int i = 0;
Node<K,V>[] tab = table;
while (tab != null && i < tab.length) {
Node<K,V> f = tabAt(tab, i);
if (f == null)
++i;
else if (f.hash < 0) {
Object fk;
if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
try {
if (tabAt(tab, i) == f) {
for (Node<K,V> p = t.first; p != null; p = p.next)
--delta;
t.first = null;
t.root = null;
++i;
}
} finally {
t.unlockWrite(stamp);
}
}
else
tab = (Node<K,V>[])fk;
}
else {
synchronized (f) {
if (tabAt(tab, i) == f) {
for (Node<K,V> e = f; e != null; e = e.next)
--delta;
setTabAt(tab, i, null);
++i;
}
}
}
}
if (delta != 0L)
addCount(delta, -1);
}
/* ---------------- Table Initialization and Resizing -------------- */
/**
* Returns a power of two table size for the given desired capacity.
* See Hackers Delight, sec 3.2
*/
private static final int tableSizeFor(int c) {
int n = c - 1;
n |= n >>> 1;
n |= n >>> 2;
n |= n >>> 4;
n |= n >>> 8;
n |= n >>> 16;
return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
}
/**
* Initializes table, using the size recorded in sizeCtl.
*/
private final Node<K,V>[] initTable() {
Node<K,V>[] tab; int sc;
while ((tab = table) == null) {
if ((sc = sizeCtl) < 0)
Thread.yield(); // lost initialization race; just spin
else if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
try {
if ((tab = table) == null) {
int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
table = tab = (Node<K,V>[])new Node[n];
sc = n - (n >>> 2);
}
} finally {
sizeCtl = sc;
}
break;
}
}
return tab;
}
/**
* Adds to count, and if table is too small and not already
* resizing, initiates transfer. If already resizing, helps
* perform transfer if work is available. Rechecks occupancy
* after a transfer to see if another resize is already needed
* because resizings are lagging additions.
*
* @param x the count to add
* @param check if <0, don't check resize, if <= 1 only check if uncontended
*/
private final void addCount(long x, int check) {
Cell[] as; long b, s;
if ((as = counterCells) != null ||
!U.compareAndSwapLong(this, BASECOUNT, b = baseCount, s = b + x)) {
Cell a; long v; int m;
boolean uncontended = true;
if (as == null || (m = as.length - 1) < 0 ||
(a = as[ThreadLocalRandom.getProbe() & m]) == null ||
!(uncontended =
U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))) {
fullAddCount(x, uncontended);
return;
}
if (check <= 1)
return;
s = sumCount();
}
if (check >= 0) {
Node<K,V>[] tab, nt; int sc;
while (s >= (long)(sc = sizeCtl) && (tab = table) != null &&
tab.length < MAXIMUM_CAPACITY) {
if (sc < 0) {
if (sc == -1 || transferIndex <= transferOrigin ||
(nt = nextTable) == null)
break;
if (U.compareAndSwapInt(this, SIZECTL, sc, sc - 1))
transfer(tab, nt);
}
else if (U.compareAndSwapInt(this, SIZECTL, sc, -2))
transfer(tab, null);
s = sumCount();
}
}
}
/**
* Tries to presize table to accommodate the given number of elements.
*
* @param size number of elements (doesn't need to be perfectly accurate)
*/
private final void tryPresize(int size) {
int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
tableSizeFor(size + (size >>> 1) + 1);
int sc;
while ((sc = sizeCtl) >= 0) {
Node<K,V>[] tab = table; int n;
if (tab == null || (n = tab.length) == 0) {
n = (sc > c) ? sc : c;
if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
try {
if (table == tab) {
table = (Node<K,V>[])new Node[n];
sc = n - (n >>> 2);
}
} finally {
sizeCtl = sc;
}
}
}
else if (c <= sc || n >= MAXIMUM_CAPACITY)
break;
else if (tab == table &&
U.compareAndSwapInt(this, SIZECTL, sc, -2))
transfer(tab, null);
}
}
/**
* Moves and/or copies the nodes in each bin to new table. See
* above for explanation.
*/
private final void transfer(Node<K,V>[] tab, Node<K,V>[] nextTab) {
int n = tab.length, stride;
if ((stride = (NCPU > 1) ? (n >>> 3) / NCPU : n) < MIN_TRANSFER_STRIDE)
stride = MIN_TRANSFER_STRIDE; // subdivide range
if (nextTab == null) { // initiating
try {
nextTab = (Node<K,V>[])new Node[n << 1];
} catch (Throwable ex) { // try to cope with OOME
sizeCtl = Integer.MAX_VALUE;
return;
}
nextTable = nextTab;
transferOrigin = n;
transferIndex = n;
Node<K,V> rev = new Node<K,V>(MOVED, tab, null, null);
for (int k = n; k > 0;) { // progressively reveal ready slots
int nextk = (k > stride) ? k - stride : 0;
for (int m = nextk; m < k; ++m)
nextTab[m] = rev;
for (int m = n + nextk; m < n + k; ++m)
nextTab[m] = rev;
U.putOrderedInt(this, TRANSFERORIGIN, k = nextk);
}
}
int nextn = nextTab.length;
Node<K,V> fwd = new Node<K,V>(MOVED, nextTab, null, null);
boolean advance = true;
for (int i = 0, bound = 0;;) {
int nextIndex, nextBound; Node<K,V> f; Object fk;
while (advance) {
if (--i >= bound)
advance = false;
else if ((nextIndex = transferIndex) <= transferOrigin) {
i = -1;
advance = false;
}
else if (U.compareAndSwapInt
(this, TRANSFERINDEX, nextIndex,
nextBound = (nextIndex > stride ?
nextIndex - stride : 0))) {
bound = nextBound;
i = nextIndex - 1;
advance = false;
}
}
if (i < 0 || i >= n || i + n >= nextn) {
for (int sc;;) {
if (U.compareAndSwapInt(this, SIZECTL, sc = sizeCtl, ++sc)) {
if (sc == -1) {
nextTable = null;
table = nextTab;
sizeCtl = (n << 1) - (n >>> 1);
}
return;
}
}
}
else if ((f = tabAt(tab, i)) == null) {
if (casTabAt(tab, i, null, fwd)) {
setTabAt(nextTab, i, null);
setTabAt(nextTab, i + n, null);
advance = true;
}
}
else if (f.hash >= 0) {
synchronized (f) {
if (tabAt(tab, i) == f) {
int runBit = f.hash & n;
Node<K,V> lastRun = f, lo = null, hi = null;
for (Node<K,V> p = f.next; p != null; p = p.next) {
int b = p.hash & n;
if (b != runBit) {
runBit = b;
lastRun = p;
}
}
if (runBit == 0)
lo = lastRun;
else
hi = lastRun;
for (Node<K,V> p = f; p != lastRun; p = p.next) {
int ph = p.hash; Object pk = p.key; V pv = p.val;
if ((ph & n) == 0)
lo = new Node<K,V>(ph, pk, pv, lo);
else
hi = new Node<K,V>(ph, pk, pv, hi);
}
setTabAt(nextTab, i, lo);
setTabAt(nextTab, i + n, hi);
setTabAt(tab, i, fwd);
advance = true;
}
}
}
else if ((fk = f.key) instanceof TreeBin) {
TreeBin<K,V> t = (TreeBin<K,V>)fk;
long stamp = t.writeLock();
try {
if (tabAt(tab, i) == f) {
TreeNode<K,V> root;
Node<K,V> ln = null, hn = null;
if ((root = t.root) != null) {
Node<K,V> e, p; TreeNode<K,V> lr, rr; int lh;
TreeBin<K,V> lt = null, ht = null;
for (lr = root; lr.left != null; lr = lr.left);
for (rr = root; rr.right != null; rr = rr.right);
if ((lh = lr.hash) == rr.hash) { // move entire tree
if ((lh & n) == 0)
lt = t;
else
ht = t;
}
else {
lt = new TreeBin<K,V>();
ht = new TreeBin<K,V>();
int lc = 0, hc = 0;
for (e = t.first; e != null; e = e.next) {
int h = e.hash;
Object k = e.key; V v = e.val;
if ((h & n) == 0) {
++lc;
lt.putTreeNode(h, k, v);
}
else {
++hc;
ht.putTreeNode(h, k, v);
}
}
if (lc < TREE_THRESHOLD) { // throw away
for (p = lt.first; p != null; p = p.next)
ln = new Node<K,V>(p.hash, p.key,
p.val, ln);
lt = null;
}
if (hc < TREE_THRESHOLD) {
for (p = ht.first; p != null; p = p.next)
hn = new Node<K,V>(p.hash, p.key,
p.val, hn);
ht = null;
}
}
if (ln == null && lt != null)
ln = new Node<K,V>(MOVED, lt, null, null);
if (hn == null && ht != null)
hn = new Node<K,V>(MOVED, ht, null, null);
}
setTabAt(nextTab, i, ln);
setTabAt(nextTab, i + n, hn);
setTabAt(tab, i, fwd);
advance = true;
}
} finally {
t.unlockWrite(stamp);
}
}
else
advance = true; // already processed
}
}
/* ---------------- Counter support -------------- */
final long sumCount() {
Cell[] as = counterCells; Cell a;
long sum = baseCount;
if (as != null) {
for (int i = 0; i < as.length; ++i) {
if ((a = as[i]) != null)
sum += a.value;
}
}
return sum;
}
// See LongAdder version for explanation
private final void fullAddCount(long x, boolean wasUncontended) {
int h;
if ((h = ThreadLocalRandom.getProbe()) == 0) {
ThreadLocalRandom.localInit(); // force initialization
h = ThreadLocalRandom.getProbe();
wasUncontended = true;
}
boolean collide = false; // True if last slot nonempty
for (;;) {
Cell[] as; Cell a; int n; long v;
if ((as = counterCells) != null && (n = as.length) > 0) {
if ((a = as[(n - 1) & h]) == null) {
if (cellsBusy == 0) { // Try to attach new Cell
Cell r = new Cell(x); // Optimistic create
if (cellsBusy == 0 &&
U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
boolean created = false;
try { // Recheck under lock
Cell[] rs; int m, j;
if ((rs = counterCells) != null &&
(m = rs.length) > 0 &&
rs[j = (m - 1) & h] == null) {
rs[j] = r;
created = true;
}
} finally {
cellsBusy = 0;
}
if (created)
break;
continue; // Slot is now non-empty
}
}
collide = false;
}
else if (!wasUncontended) // CAS already known to fail
wasUncontended = true; // Continue after rehash
else if (U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))
break;
else if (counterCells != as || n >= NCPU)
collide = false; // At max size or stale
else if (!collide)
collide = true;
else if (cellsBusy == 0 &&
U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
try {
if (counterCells == as) {// Expand table unless stale
Cell[] rs = new Cell[n << 1];
for (int i = 0; i < n; ++i)
rs[i] = as[i];
counterCells = rs;
}
} finally {
cellsBusy = 0;
}
collide = false;
continue; // Retry with expanded table
}
h = ThreadLocalRandom.advanceProbe(h);
}
else if (cellsBusy == 0 && counterCells == as &&
U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
boolean init = false;
try { // Initialize table
if (counterCells == as) {
Cell[] rs = new Cell[2];
rs[h & 1] = new Cell(x);
counterCells = rs;
init = true;
}
} finally {
cellsBusy = 0;
}
if (init)
break;
}
else if (U.compareAndSwapLong(this, BASECOUNT, v = baseCount, v + x))
break; // Fall back on using base
}
}
/* ----------------Table Traversal -------------- */
/**
* Encapsulates traversal for methods such as containsValue; also
* serves as a base class for other iterators and spliterators.
*
* Method advance visits once each still-valid node that was
* reachable upon iterator construction. It might miss some that
* were added to a bin after the bin was visited, which is OK wrt
* consistency guarantees. Maintaining this property in the face
* of possible ongoing resizes requires a fair amount of
* bookkeeping state that is difficult to optimize away amidst
* volatile accesses. Even so, traversal maintains reasonable
* throughput.
*
* Normally, iteration proceeds bin-by-bin traversing lists.
* However, if the table has been resized, then all future steps
* must traverse both the bin at the current index as well as at
* (index + baseSize); and so on for further resizings. To
* paranoically cope with potential sharing by users of iterators
* across threads, iteration terminates if a bounds checks fails
* for a table read.
*/
static class Traverser<K,V> {
Node<K,V>[] tab; // current table; updated if resized
Node<K,V> next; // the next entry to use
int index; // index of bin to use next
int baseIndex; // current index of initial table
int baseLimit; // index bound for initial table
final int baseSize; // initial table size
Traverser(Node<K,V>[] tab, int size, int index, int limit) {
this.tab = tab;
this.baseSize = size;
this.baseIndex = this.index = index;
this.baseLimit = limit;
this.next = null;
}
/**
* Advances if possible, returning next valid node, or null if none.
*/
final Node<K,V> advance() {
Node<K,V> e;
if ((e = next) != null)
e = e.next;
for (;;) {
Node<K,V>[] t; int i, n; Object ek; // must use locals in checks
if (e != null)
return next = e;
if (baseIndex >= baseLimit || (t = tab) == null ||
(n = t.length) <= (i = index) || i < 0)
return next = null;
if ((e = tabAt(t, index)) != null && e.hash < 0) {
if ((ek = e.key) instanceof TreeBin)
e = ((TreeBin<K,V>)ek).first;
else {
tab = (Node<K,V>[])ek;
e = null;
continue;
}
}
if ((index += baseSize) >= n)
index = ++baseIndex; // visit upper slots if present
}
}
}
/**
* Base of key, value, and entry Iterators. Adds fields to
* Traverser to support iterator.remove
*/
static class BaseIterator<K,V> extends Traverser<K,V> {
final ConcurrentHashMap<K,V> map;
Node<K,V> lastReturned;
BaseIterator(Node<K,V>[] tab, int size, int index, int limit,
ConcurrentHashMap<K,V> map) {
super(tab, size, index, limit);
this.map = map;
advance();
}
public final boolean hasNext() { return next != null; }
public final boolean hasMoreElements() { return next != null; }
public final void remove() {
Node<K,V> p;
if ((p = lastReturned) == null)
throw new IllegalStateException();
lastReturned = null;
map.internalReplace((K)p.key, null, null);
}
}
static final class KeyIterator<K,V> extends BaseIterator<K,V>
implements Iterator<K>, Enumeration<K> {
KeyIterator(Node<K,V>[] tab, int index, int size, int limit,
ConcurrentHashMap<K,V> map) {
super(tab, index, size, limit, map);
}
public final K next() {
Node<K,V> p;
if ((p = next) == null)
throw new NoSuchElementException();
K k = (K)p.key;
lastReturned = p;
advance();
return k;
}
public final K nextElement() { return next(); }
}
static final class ValueIterator<K,V> extends BaseIterator<K,V>
implements Iterator<V>, Enumeration<V> {
ValueIterator(Node<K,V>[] tab, int index, int size, int limit,
ConcurrentHashMap<K,V> map) {
super(tab, index, size, limit, map);
}
public final V next() {
Node<K,V> p;
if ((p = next) == null)
throw new NoSuchElementException();
V v = p.val;
lastReturned = p;
advance();
return v;
}
public final V nextElement() { return next(); }
}
static final class EntryIterator<K,V> extends BaseIterator<K,V>
implements Iterator<Map.Entry<K,V>> {
EntryIterator(Node<K,V>[] tab, int index, int size, int limit,
ConcurrentHashMap<K,V> map) {
super(tab, index, size, limit, map);
}
public final Map.Entry<K,V> next() {
Node<K,V> p;
if ((p = next) == null)
throw new NoSuchElementException();
K k = (K)p.key;
V v = p.val;
lastReturned = p;
advance();
return new MapEntry<K,V>(k, v, map);
}
}
static final class KeySpliterator<K,V> extends Traverser<K,V>
implements Spliterator<K> {
long est; // size estimate
KeySpliterator(Node<K,V>[] tab, int size, int index, int limit,
long est) {
super(tab, size, index, limit);
this.est = est;
}
public Spliterator<K> trySplit() {
int i, f, h;
return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
new KeySpliterator<K,V>(tab, baseSize, baseLimit = h,
f, est >>>= 1);
}
public void forEachRemaining(Consumer<? super K> action) {
if (action == null) throw new NullPointerException();
for (Node<K,V> p; (p = advance()) != null;)
action.accept((K)p.key);
}
public boolean tryAdvance(Consumer<? super K> action) {
if (action == null) throw new NullPointerException();
Node<K,V> p;
if ((p = advance()) == null)
return false;
action.accept((K)p.key);
return true;
}
public long estimateSize() { return est; }
public int characteristics() {
return Spliterator.DISTINCT | Spliterator.CONCURRENT |
Spliterator.NONNULL;
}
}
static final class ValueSpliterator<K,V> extends Traverser<K,V>
implements Spliterator<V> {
long est; // size estimate
ValueSpliterator(Node<K,V>[] tab, int size, int index, int limit,
long est) {
super(tab, size, index, limit);
this.est = est;
}
public Spliterator<V> trySplit() {
int i, f, h;
return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
new ValueSpliterator<K,V>(tab, baseSize, baseLimit = h,
f, est >>>= 1);
}
public void forEachRemaining(Consumer<? super V> action) {
if (action == null) throw new NullPointerException();
for (Node<K,V> p; (p = advance()) != null;)
action.accept(p.val);
}
public boolean tryAdvance(Consumer<? super V> action) {
if (action == null) throw new NullPointerException();
Node<K,V> p;
if ((p = advance()) == null)
return false;
action.accept(p.val);
return true;
}
public long estimateSize() { return est; }
public int characteristics() {
return Spliterator.CONCURRENT | Spliterator.NONNULL;
}
}
static final class EntrySpliterator<K,V> extends Traverser<K,V>
implements Spliterator<Map.Entry<K,V>> {
final ConcurrentHashMap<K,V> map; // To export MapEntry
long est; // size estimate
EntrySpliterator(Node<K,V>[] tab, int size, int index, int limit,
long est, ConcurrentHashMap<K,V> map) {
super(tab, size, index, limit);
this.map = map;
this.est = est;
}
public Spliterator<Map.Entry<K,V>> trySplit() {
int i, f, h;
return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
new EntrySpliterator<K,V>(tab, baseSize, baseLimit = h,
f, est >>>= 1, map);
}
public void forEachRemaining(Consumer<? super Map.Entry<K,V>> action) {
if (action == null) throw new NullPointerException();
for (Node<K,V> p; (p = advance()) != null; )
action.accept(new MapEntry<K,V>((K)p.key, p.val, map));
}
public boolean tryAdvance(Consumer<? super Map.Entry<K,V>> action) {
if (action == null) throw new NullPointerException();
Node<K,V> p;
if ((p = advance()) == null)
return false;
action.accept(new MapEntry<K,V>((K)p.key, p.val, map));
return true;
}
public long estimateSize() { return est; }
public int characteristics() {
return Spliterator.DISTINCT | Spliterator.CONCURRENT |
Spliterator.NONNULL;
}
}
/* ---------------- Public operations -------------- */
/**
* Creates a new, empty map with the default initial table size (16).
*/
public ConcurrentHashMap() {
}
/**
* Creates a new, empty map with an initial table size
* accommodating the specified number of elements without the need
* to dynamically resize.
*
* @param initialCapacity The implementation performs internal
* sizing to accommodate this many elements.
* @throws IllegalArgumentException if the initial capacity of
* elements is negative
*/
public ConcurrentHashMap(int initialCapacity) {
if (initialCapacity < 0)
throw new IllegalArgumentException();
int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
MAXIMUM_CAPACITY :
tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
this.sizeCtl = cap;
}
/**
* Creates a new map with the same mappings as the given map.
*
* @param m the map
*/
public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
this.sizeCtl = DEFAULT_CAPACITY;
internalPutAll(m);
}
/**
* Creates a new, empty map with an initial table size based on
* the given number of elements ({@code initialCapacity}) and
* initial table density ({@code loadFactor}).
*
* @param initialCapacity the initial capacity. The implementation
* performs internal sizing to accommodate this many elements,
* given the specified load factor.
* @param loadFactor the load factor (table density) for
* establishing the initial table size
* @throws IllegalArgumentException if the initial capacity of
* elements is negative or the load factor is nonpositive
*
* @since 1.6
*/
public ConcurrentHashMap(int initialCapacity, float loadFactor) {
this(initialCapacity, loadFactor, 1);
}
/**
* Creates a new, empty map with an initial table size based on
* the given number of elements ({@code initialCapacity}), table
* density ({@code loadFactor}), and number of concurrently
* updating threads ({@code concurrencyLevel}).
*
* @param initialCapacity the initial capacity. The implementation
* performs internal sizing to accommodate this many elements,
* given the specified load factor.
* @param loadFactor the load factor (table density) for
* establishing the initial table size
* @param concurrencyLevel the estimated number of concurrently
* updating threads. The implementation may use this value as
* a sizing hint.
* @throws IllegalArgumentException if the initial capacity is
* negative or the load factor or concurrencyLevel are
* nonpositive
*/
public ConcurrentHashMap(int initialCapacity,
float loadFactor, int concurrencyLevel) {
if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
throw new IllegalArgumentException();
if (initialCapacity < concurrencyLevel) // Use at least as many bins
initialCapacity = concurrencyLevel; // as estimated threads
long size = (long)(1.0 + (long)initialCapacity / loadFactor);
int cap = (size >= (long)MAXIMUM_CAPACITY) ?
MAXIMUM_CAPACITY : tableSizeFor((int)size);
this.sizeCtl = cap;
}
/**
* Creates a new {@link Set} backed by a ConcurrentHashMap
* from the given type to {@code Boolean.TRUE}.
*
* @return the new set
* @since 1.8
*/
public static <K> KeySetView<K,Boolean> newKeySet() {
return new KeySetView<K,Boolean>
(new ConcurrentHashMap<K,Boolean>(), Boolean.TRUE);
}
/**
* Creates a new {@link Set} backed by a ConcurrentHashMap
* from the given type to {@code Boolean.TRUE}.
*
* @param initialCapacity The implementation performs internal
* sizing to accommodate this many elements.
* @throws IllegalArgumentException if the initial capacity of
* elements is negative
* @return the new set
* @since 1.8
*/
public static <K> KeySetView<K,Boolean> newKeySet(int initialCapacity) {
return new KeySetView<K,Boolean>
(new ConcurrentHashMap<K,Boolean>(initialCapacity), Boolean.TRUE);
}
/**
* Returns {@code true} if this map contains no key-value mappings.
*
* @return {@code true} if this map contains no key-value mappings
*/
public boolean isEmpty() {
return sumCount() <= 0L; // ignore transient negative values
}
/**
* Returns the number of key-value mappings in this map. If the
* map contains more than {@code Integer.MAX_VALUE} elements, returns
* {@code Integer.MAX_VALUE}.
*
* @return the number of key-value mappings in this map
*/
public int size() {
long n = sumCount();
return ((n < 0L) ? 0 :
(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
(int)n);
}
/**
* Returns the number of mappings. This method should be used
* instead of {@link #size} because a ConcurrentHashMap may
* contain more mappings than can be represented as an int. The
* value returned is an estimate; the actual count may differ if
* there are concurrent insertions or removals.
*
* @return the number of mappings
* @since 1.8
*/
public long mappingCount() {
long n = sumCount();
return (n < 0L) ? 0L : n; // ignore transient negative values
}
/**
* Returns the value to which the specified key is mapped,
* or {@code null} if this map contains no mapping for the key.
*
* <p>More formally, if this map contains a mapping from a key
* {@code k} to a value {@code v} such that {@code key.equals(k)},
* then this method returns {@code v}; otherwise it returns
* {@code null}. (There can be at most one such mapping.)
*
* @throws NullPointerException if the specified key is null
*/
public V get(Object key) {
return internalGet(key);
}
/**
* Returns the value to which the specified key is mapped, or the
* given default value if this map contains no mapping for the
* key.
*
* @param key the key whose associated value is to be returned
* @param defaultValue the value to return if this map contains
* no mapping for the given key
* @return the mapping for the key, if present; else the default value
* @throws NullPointerException if the specified key is null
*/
public V getOrDefault(Object key, V defaultValue) {
V v;
return (v = internalGet(key)) == null ? defaultValue : v;
}
/**
* Tests if the specified object is a key in this table.
*
* @param key possible key
* @return {@code true} if and only if the specified object
* is a key in this table, as determined by the
* {@code equals} method; {@code false} otherwise
* @throws NullPointerException if the specified key is null
*/
public boolean containsKey(Object key) {
return internalGet(key) != null;
}
/**
* Returns {@code true} if this map maps one or more keys to the
* specified value. Note: This method may require a full traversal
* of the map, and is much slower than method {@code containsKey}.
*
* @param value value whose presence in this map is to be tested
* @return {@code true} if this map maps one or more keys to the
* specified value
* @throws NullPointerException if the specified value is null
*/
public boolean containsValue(Object value) {
if (value == null)
throw new NullPointerException();
Node<K,V>[] t;
if ((t = table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; ) {
V v;
if ((v = p.val) == value || value.equals(v))
return true;
}
}
return false;
}
/**
* Legacy method testing if some key maps into the specified value
* in this table. This method is identical in functionality to
* {@link #containsValue(Object)}, and exists solely to ensure
* full compatibility with class {@link java.util.Hashtable},
* which supported this method prior to introduction of the
* Java Collections framework.
*
* @param value a value to search for
* @return {@code true} if and only if some key maps to the
* {@code value} argument in this table as
* determined by the {@code equals} method;
* {@code false} otherwise
* @throws NullPointerException if the specified value is null
*/
public boolean contains(Object value) {
return containsValue(value);
}
/**
* Maps the specified key to the specified value in this table.
* Neither the key nor the value can be null.
*
* <p>The value can be retrieved by calling the {@code get} method
* with a key that is equal to the original key.
*
* @param key key with which the specified value is to be associated
* @param value value to be associated with the specified key
* @return the previous value associated with {@code key}, or
* {@code null} if there was no mapping for {@code key}
* @throws NullPointerException if the specified key or value is null
*/
public V put(K key, V value) {
return internalPut(key, value, false);
}
/**
* {@inheritDoc}
*
* @return the previous value associated with the specified key,
* or {@code null} if there was no mapping for the key
* @throws NullPointerException if the specified key or value is null
*/
public V putIfAbsent(K key, V value) {
return internalPut(key, value, true);
}
/**
* Copies all of the mappings from the specified map to this one.
* These mappings replace any mappings that this map had for any of the
* keys currently in the specified map.
*
* @param m mappings to be stored in this map
*/
public void putAll(Map<? extends K, ? extends V> m) {
internalPutAll(m);
}
/**
* If the specified key is not already associated with a value,
* attempts to compute its value using the given mapping function
* and enters it into this map unless {@code null}. The entire
* method invocation is performed atomically, so the function is
* applied at most once per key. Some attempted update operations
* on this map by other threads may be blocked while computation
* is in progress, so the computation should be short and simple,
* and must not attempt to update any other mappings of this map.
*
* @param key key with which the specified value is to be associated
* @param mappingFunction the function to compute a value
* @return the current (existing or computed) value associated with
* the specified key, or null if the computed value is null
* @throws NullPointerException if the specified key or mappingFunction
* is null
* @throws IllegalStateException if the computation detectably
* attempts a recursive update to this map that would
* otherwise never complete
* @throws RuntimeException or Error if the mappingFunction does so,
* in which case the mapping is left unestablished
*/
public V computeIfAbsent(K key, Function<? super K, ? extends V> mappingFunction) {
return internalComputeIfAbsent(key, mappingFunction);
}
/**
* If the value for the specified key is present, attempts to
* compute a new mapping given the key and its current mapped
* value. The entire method invocation is performed atomically.
* Some attempted update operations on this map by other threads
* may be blocked while computation is in progress, so the
* computation should be short and simple, and must not attempt to
* update any other mappings of this map.
*
* @param key key with which a value may be associated
* @param remappingFunction the function to compute a value
* @return the new value associated with the specified key, or null if none
* @throws NullPointerException if the specified key or remappingFunction
* is null
* @throws IllegalStateException if the computation detectably
* attempts a recursive update to this map that would
* otherwise never complete
* @throws RuntimeException or Error if the remappingFunction does so,
* in which case the mapping is unchanged
*/
public V computeIfPresent(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
return internalCompute(key, true, remappingFunction);
}
/**
* Attempts to compute a mapping for the specified key and its
* current mapped value (or {@code null} if there is no current
* mapping). The entire method invocation is performed atomically.
* Some attempted update operations on this map by other threads
* may be blocked while computation is in progress, so the
* computation should be short and simple, and must not attempt to
* update any other mappings of this Map.
*
* @param key key with which the specified value is to be associated
* @param remappingFunction the function to compute a value
* @return the new value associated with the specified key, or null if none
* @throws NullPointerException if the specified key or remappingFunction
* is null
* @throws IllegalStateException if the computation detectably
* attempts a recursive update to this map that would
* otherwise never complete
* @throws RuntimeException or Error if the remappingFunction does so,
* in which case the mapping is unchanged
*/
public V compute(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
return internalCompute(key, false, remappingFunction);
}
/**
* If the specified key is not already associated with a
* (non-null) value, associates it with the given value.
* Otherwise, replaces the value with the results of the given
* remapping function, or removes if {@code null}. The entire
* method invocation is performed atomically. Some attempted
* update operations on this map by other threads may be blocked
* while computation is in progress, so the computation should be
* short and simple, and must not attempt to update any other
* mappings of this Map.
*
* @param key key with which the specified value is to be associated
* @param value the value to use if absent
* @param remappingFunction the function to recompute a value if present
* @return the new value associated with the specified key, or null if none
* @throws NullPointerException if the specified key or the
* remappingFunction is null
* @throws RuntimeException or Error if the remappingFunction does so,
* in which case the mapping is unchanged
*/
public V merge(K key, V value, BiFunction<? super V, ? super V, ? extends V> remappingFunction) {
return internalMerge(key, value, remappingFunction);
}
/**
* Removes the key (and its corresponding value) from this map.
* This method does nothing if the key is not in the map.
*
* @param key the key that needs to be removed
* @return the previous value associated with {@code key}, or
* {@code null} if there was no mapping for {@code key}
* @throws NullPointerException if the specified key is null
*/
public V remove(Object key) {
return internalReplace(key, null, null);
}
/**
* {@inheritDoc}
*
* @throws NullPointerException if the specified key is null
*/
public boolean remove(Object key, Object value) {
if (key == null)
throw new NullPointerException();
return value != null && internalReplace(key, null, value) != null;
}
/**
* {@inheritDoc}
*
* @throws NullPointerException if any of the arguments are null
*/
public boolean replace(K key, V oldValue, V newValue) {
if (key == null || oldValue == null || newValue == null)
throw new NullPointerException();
return internalReplace(key, newValue, oldValue) != null;
}
/**
* {@inheritDoc}
*
* @return the previous value associated with the specified key,
* or {@code null} if there was no mapping for the key
* @throws NullPointerException if the specified key or value is null
*/
public V replace(K key, V value) {
if (key == null || value == null)
throw new NullPointerException();
return internalReplace(key, value, null);
}
/**
* Removes all of the mappings from this map.
*/
public void clear() {
internalClear();
}
/**
* Returns a {@link Set} view of the keys contained in this map.
* The set is backed by the map, so changes to the map are
* reflected in the set, and vice-versa. The set supports element
* removal, which removes the corresponding mapping from this map,
* via the {@code Iterator.remove}, {@code Set.remove},
* {@code removeAll}, {@code retainAll}, and {@code clear}
* operations. It does not support the {@code add} or
* {@code addAll} operations.
*
* <p>The view's {@code iterator} is a "weakly consistent" iterator
* that will never throw {@link ConcurrentModificationException},
* and guarantees to traverse elements as they existed upon
* construction of the iterator, and may (but is not guaranteed to)
* reflect any modifications subsequent to construction.
*
* @return the set view
*/
public KeySetView<K,V> keySet() {
KeySetView<K,V> ks = keySet;
return (ks != null) ? ks : (keySet = new KeySetView<K,V>(this, null));
}
/**
* Returns a {@link Set} view of the keys in this map, using the
* given common mapped value for any additions (i.e., {@link
* Collection#add} and {@link Collection#addAll(Collection)}).
* This is of course only appropriate if it is acceptable to use
* the same value for all additions from this view.
*
* @param mappedValue the mapped value to use for any additions
* @return the set view
* @throws NullPointerException if the mappedValue is null
*/
public KeySetView<K,V> keySet(V mappedValue) {
if (mappedValue == null)
throw new NullPointerException();
return new KeySetView<K,V>(this, mappedValue);
}
/**
* Returns a {@link Collection} view of the values contained in this map.
* The collection is backed by the map, so changes to the map are
* reflected in the collection, and vice-versa. The collection
* supports element removal, which removes the corresponding
* mapping from this map, via the {@code Iterator.remove},
* {@code Collection.remove}, {@code removeAll},
* {@code retainAll}, and {@code clear} operations. It does not
* support the {@code add} or {@code addAll} operations.
*
* <p>The view's {@code iterator} is a "weakly consistent" iterator
* that will never throw {@link ConcurrentModificationException},
* and guarantees to traverse elements as they existed upon
* construction of the iterator, and may (but is not guaranteed to)
* reflect any modifications subsequent to construction.
*
* @return the collection view
*/
public Collection<V> values() {
ValuesView<K,V> vs = values;
return (vs != null) ? vs : (values = new ValuesView<K,V>(this));
}
/**
* Returns a {@link Set} view of the mappings contained in this map.
* The set is backed by the map, so changes to the map are
* reflected in the set, and vice-versa. The set supports element
* removal, which removes the corresponding mapping from the map,
* via the {@code Iterator.remove}, {@code Set.remove},
* {@code removeAll}, {@code retainAll}, and {@code clear}
* operations.
*
* <p>The view's {@code iterator} is a "weakly consistent" iterator
* that will never throw {@link ConcurrentModificationException},
* and guarantees to traverse elements as they existed upon
* construction of the iterator, and may (but is not guaranteed to)
* reflect any modifications subsequent to construction.
*
* @return the set view
*/
public Set<Map.Entry<K,V>> entrySet() {
EntrySetView<K,V> es = entrySet;
return (es != null) ? es : (entrySet = new EntrySetView<K,V>(this));
}
/**
* Returns an enumeration of the keys in this table.
*
* @return an enumeration of the keys in this table
* @see #keySet()
*/
public Enumeration<K> keys() {
Node<K,V>[] t;
int f = (t = table) == null ? 0 : t.length;
return new KeyIterator<K,V>(t, f, 0, f, this);
}
/**
* Returns an enumeration of the values in this table.
*
* @return an enumeration of the values in this table
* @see #values()
*/
public Enumeration<V> elements() {
Node<K,V>[] t;
int f = (t = table) == null ? 0 : t.length;
return new ValueIterator<K,V>(t, f, 0, f, this);
}
/**
* Returns the hash code value for this {@link Map}, i.e.,
* the sum of, for each key-value pair in the map,
* {@code key.hashCode() ^ value.hashCode()}.
*
* @return the hash code value for this map
*/
public int hashCode() {
int h = 0;
Node<K,V>[] t;
if ((t = table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; )
h += p.key.hashCode() ^ p.val.hashCode();
}
return h;
}
/**
* Returns a string representation of this map. The string
* representation consists of a list of key-value mappings (in no
* particular order) enclosed in braces ("{@code {}}"). Adjacent
* mappings are separated by the characters {@code ", "} (comma
* and space). Each key-value mapping is rendered as the key
* followed by an equals sign ("{@code =}") followed by the
* associated value.
*
* @return a string representation of this map
*/
public String toString() {
Node<K,V>[] t;
int f = (t = table) == null ? 0 : t.length;
Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
StringBuilder sb = new StringBuilder();
sb.append('{');
Node<K,V> p;
if ((p = it.advance()) != null) {
for (;;) {
K k = (K)p.key;
V v = p.val;
sb.append(k == this ? "(this Map)" : k);
sb.append('=');
sb.append(v == this ? "(this Map)" : v);
if ((p = it.advance()) == null)
break;
sb.append(',').append(' ');
}
}
return sb.append('}').toString();
}
/**
* Compares the specified object with this map for equality.
* Returns {@code true} if the given object is a map with the same
* mappings as this map. This operation may return misleading
* results if either map is concurrently modified during execution
* of this method.
*
* @param o object to be compared for equality with this map
* @return {@code true} if the specified object is equal to this map
*/
public boolean equals(Object o) {
if (o != this) {
if (!(o instanceof Map))
return false;
Map<?,?> m = (Map<?,?>) o;
Node<K,V>[] t;
int f = (t = table) == null ? 0 : t.length;
Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
for (Node<K,V> p; (p = it.advance()) != null; ) {
V val = p.val;
Object v = m.get(p.key);
if (v == null || (v != val && !v.equals(val)))
return false;
}
for (Map.Entry<?,?> e : m.entrySet()) {
Object mk, mv, v;
if ((mk = e.getKey()) == null ||
(mv = e.getValue()) == null ||
(v = internalGet(mk)) == null ||
(mv != v && !mv.equals(v)))
return false;
}
}
return true;
}
/* ---------------- Serialization Support -------------- */
/**
* Stripped-down version of helper class used in previous version,
* declared for the sake of serialization compatibility
*/
static class Segment<K,V> extends ReentrantLock implements Serializable {
private static final long serialVersionUID = 2249069246763182397L;
final float loadFactor;
Segment(float lf) { this.loadFactor = lf; }
}
/**
* Saves the state of the {@code ConcurrentHashMap} instance to a
* stream (i.e., serializes it).
* @param s the stream
* @serialData
* the key (Object) and value (Object)
* for each key-value mapping, followed by a null pair.
* The key-value mappings are emitted in no particular order.
*/
private void writeObject(java.io.ObjectOutputStream s)
throws java.io.IOException {
// For serialization compatibility
// Emulate segment calculation from previous version of this class
int sshift = 0;
int ssize = 1;
while (ssize < DEFAULT_CONCURRENCY_LEVEL) {
++sshift;
ssize <<= 1;
}
int segmentShift = 32 - sshift;
int segmentMask = ssize - 1;
Segment<K,V>[] segments = (Segment<K,V>[])
new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
for (int i = 0; i < segments.length; ++i)
segments[i] = new Segment<K,V>(LOAD_FACTOR);
s.putFields().put("segments", segments);
s.putFields().put("segmentShift", segmentShift);
s.putFields().put("segmentMask", segmentMask);
s.writeFields();
Node<K,V>[] t;
if ((t = table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; ) {
s.writeObject(p.key);
s.writeObject(p.val);
}
}
s.writeObject(null);
s.writeObject(null);
segments = null; // throw away
}
/**
* Reconstitutes the instance from a stream (that is, deserializes it).
* @param s the stream
*/
private void readObject(java.io.ObjectInputStream s)
throws java.io.IOException, ClassNotFoundException {
s.defaultReadObject();
// Create all nodes, then place in table once size is known
long size = 0L;
Node<K,V> p = null;
for (;;) {
K k = (K) s.readObject();
V v = (V) s.readObject();
if (k != null && v != null) {
int h = spread(k.hashCode());
p = new Node<K,V>(h, k, v, p);
++size;
}
else
break;
}
if (p != null) {
boolean init = false;
int n;
if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
n = MAXIMUM_CAPACITY;
else {
int sz = (int)size;
n = tableSizeFor(sz + (sz >>> 1) + 1);
}
int sc = sizeCtl;
boolean collide = false;
if (n > sc &&
U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
try {
if (table == null) {
init = true;
Node<K,V>[] tab = (Node<K,V>[])new Node[n];
int mask = n - 1;
while (p != null) {
int j = p.hash & mask;
Node<K,V> next = p.next;
Node<K,V> q = p.next = tabAt(tab, j);
setTabAt(tab, j, p);
if (!collide && q != null && q.hash == p.hash)
collide = true;
p = next;
}
table = tab;
addCount(size, -1);
sc = n - (n >>> 2);
}
} finally {
sizeCtl = sc;
}
if (collide) { // rescan and convert to TreeBins
Node<K,V>[] tab = table;
for (int i = 0; i < tab.length; ++i) {
int c = 0;
for (Node<K,V> e = tabAt(tab, i); e != null; e = e.next) {
if (++c > TREE_THRESHOLD &&
(e.key instanceof Comparable)) {
replaceWithTreeBin(tab, i, e.key);
break;
}
}
}
}
}
if (!init) { // Can only happen if unsafely published.
while (p != null) {
internalPut((K)p.key, p.val, false);
p = p.next;
}
}
}
}
// -------------------------------------------------------
// Overrides of other default Map methods
public void forEach(BiConsumer<? super K, ? super V> action) {
if (action == null) throw new NullPointerException();
Node<K,V>[] t;
if ((t = table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; ) {
action.accept((K)p.key, p.val);
}
}
}
public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function) {
if (function == null) throw new NullPointerException();
Node<K,V>[] t;
if ((t = table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; ) {
K k = (K)p.key;
internalPut(k, function.apply(k, p.val), false);
}
}
}
// -------------------------------------------------------
// Parallel bulk operations
/**
* Computes initial batch value for bulk tasks. The returned value
* is approximately exp2 of the number of times (minus one) to
* split task by two before executing leaf action. This value is
* faster to compute and more convenient to use as a guide to
* splitting than is the depth, since it is used while dividing by
* two anyway.
*/
final int batchFor(long b) {
long n;
if (b == Long.MAX_VALUE || (n = sumCount()) <= 1L || n < b)
return 0;
int sp = ForkJoinPool.getCommonPoolParallelism() << 2; // slack of 4
return (b <= 0L || (n /= b) >= sp) ? sp : (int)n;
}
/**
* Performs the given action for each (key, value).
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void forEach(long parallelismThreshold,
BiConsumer<? super K,? super V> action) {
if (action == null) throw new NullPointerException();
new ForEachMappingTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
action).invoke();
}
/**
* Performs the given action for each non-null transformation
* of each (key, value).
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @since 1.8
*/
public <U> void forEach(long parallelismThreshold,
BiFunction<? super K, ? super V, ? extends U> transformer,
Consumer<? super U> action) {
if (transformer == null || action == null)
throw new NullPointerException();
new ForEachTransformedMappingTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
transformer, action).invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each (key, value), or null if none. Upon
* success, further element processing is suppressed and the
* results of any other parallel invocations of the search
* function are ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @return a non-null result from applying the given search
* function on each (key, value), or null if none
* @since 1.8
*/
public <U> U search(long parallelismThreshold,
BiFunction<? super K, ? super V, ? extends U> searchFunction) {
if (searchFunction == null) throw new NullPointerException();
return new SearchMappingsTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
searchFunction, new AtomicReference<U>()).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public <U> U reduce(long parallelismThreshold,
BiFunction<? super K, ? super V, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceMappingsTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public double reduceToDoubleIn(long parallelismThreshold,
ToDoubleBiFunction<? super K, ? super V> transformer,
double basis,
DoubleBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceMappingsToDoubleTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public long reduceToLong(long parallelismThreshold,
ToLongBiFunction<? super K, ? super V> transformer,
long basis,
LongBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceMappingsToLongTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public int reduceToInt(long parallelismThreshold,
ToIntBiFunction<? super K, ? super V> transformer,
int basis,
IntBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceMappingsToIntTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Performs the given action for each key.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void forEachKey(long parallelismThreshold,
Consumer<? super K> action) {
if (action == null) throw new NullPointerException();
new ForEachKeyTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
action).invoke();
}
/**
* Performs the given action for each non-null transformation
* of each key.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @since 1.8
*/
public <U> void forEachKey(long parallelismThreshold,
Function<? super K, ? extends U> transformer,
Consumer<? super U> action) {
if (transformer == null || action == null)
throw new NullPointerException();
new ForEachTransformedKeyTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
transformer, action).invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each key, or null if none. Upon success,
* further element processing is suppressed and the results of
* any other parallel invocations of the search function are
* ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @return a non-null result from applying the given search
* function on each key, or null if none
* @since 1.8
*/
public <U> U searchKeys(long parallelismThreshold,
Function<? super K, ? extends U> searchFunction) {
if (searchFunction == null) throw new NullPointerException();
return new SearchKeysTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
searchFunction, new AtomicReference<U>()).invoke();
}
/**
* Returns the result of accumulating all keys using the given
* reducer to combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param reducer a commutative associative combining function
* @return the result of accumulating all keys using the given
* reducer to combine values, or null if none
* @since 1.8
*/
public K reduceKeys(long parallelismThreshold,
BiFunction<? super K, ? super K, ? extends K> reducer) {
if (reducer == null) throw new NullPointerException();
return new ReduceKeysTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, or
* null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public <U> U reduceKeys(long parallelismThreshold,
Function<? super K, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceKeysTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, and
* the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public double reduceKeysToDouble(long parallelismThreshold,
ToDoubleFunction<? super K> transformer,
double basis,
DoubleBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceKeysToDoubleTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, and
* the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public long reduceKeysToLong(long parallelismThreshold,
ToLongFunction<? super K> transformer,
long basis,
LongBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceKeysToLongTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, and
* the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public int reduceKeysToInt(long parallelismThreshold,
ToIntFunction<? super K> transformer,
int basis,
IntBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceKeysToIntTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Performs the given action for each value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void forEachValue(long parallelismThreshold,
Consumer<? super V> action) {
if (action == null)
throw new NullPointerException();
new ForEachValueTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
action).invoke();
}
/**
* Performs the given action for each non-null transformation
* of each value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @since 1.8
*/
public <U> void forEachValue(long parallelismThreshold,
Function<? super V, ? extends U> transformer,
Consumer<? super U> action) {
if (transformer == null || action == null)
throw new NullPointerException();
new ForEachTransformedValueTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
transformer, action).invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each value, or null if none. Upon success,
* further element processing is suppressed and the results of
* any other parallel invocations of the search function are
* ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @return a non-null result from applying the given search
* function on each value, or null if none
* @since 1.8
*/
public <U> U searchValues(long parallelismThreshold,
Function<? super V, ? extends U> searchFunction) {
if (searchFunction == null) throw new NullPointerException();
return new SearchValuesTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
searchFunction, new AtomicReference<U>()).invoke();
}
/**
* Returns the result of accumulating all values using the
* given reducer to combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param reducer a commutative associative combining function
* @return the result of accumulating all values
* @since 1.8
*/
public V reduceValues(long parallelismThreshold,
BiFunction<? super V, ? super V, ? extends V> reducer) {
if (reducer == null) throw new NullPointerException();
return new ReduceValuesTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values, or
* null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public <U> U reduceValues(long parallelismThreshold,
Function<? super V, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceValuesTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public double reduceValuesToDouble(long parallelismThreshold,
ToDoubleFunction<? super V> transformer,
double basis,
DoubleBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceValuesToDoubleTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public long reduceValuesToLong(long parallelismThreshold,
ToLongFunction<? super V> transformer,
long basis,
LongBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceValuesToLongTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public int reduceValuesToInt(long parallelismThreshold,
ToIntFunction<? super V> transformer,
int basis,
IntBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceValuesToIntTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Performs the given action for each entry.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void forEachEntry(long parallelismThreshold,
Consumer<? super Map.Entry<K,V>> action) {
if (action == null) throw new NullPointerException();
new ForEachEntryTask<K,V>(null, batchFor(parallelismThreshold), 0, 0, table,
action).invoke();
}
/**
* Performs the given action for each non-null transformation
* of each entry.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @since 1.8
*/
public <U> void forEachEntry(long parallelismThreshold,
Function<Map.Entry<K,V>, ? extends U> transformer,
Consumer<? super U> action) {
if (transformer == null || action == null)
throw new NullPointerException();
new ForEachTransformedEntryTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
transformer, action).invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each entry, or null if none. Upon success,
* further element processing is suppressed and the results of
* any other parallel invocations of the search function are
* ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @return a non-null result from applying the given search
* function on each entry, or null if none
* @since 1.8
*/
public <U> U searchEntries(long parallelismThreshold,
Function<Map.Entry<K,V>, ? extends U> searchFunction) {
if (searchFunction == null) throw new NullPointerException();
return new SearchEntriesTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
searchFunction, new AtomicReference<U>()).invoke();
}
/**
* Returns the result of accumulating all entries using the
* given reducer to combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param reducer a commutative associative combining function
* @return the result of accumulating all entries
* @since 1.8
*/
public Map.Entry<K,V> reduceEntries(long parallelismThreshold,
BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
if (reducer == null) throw new NullPointerException();
return new ReduceEntriesTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public <U> U reduceEntries(long parallelismThreshold,
Function<Map.Entry<K,V>, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceEntriesTask<K,V,U>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public double reduceEntriesToDouble(long parallelismThreshold,
ToDoubleFunction<Map.Entry<K,V>> transformer,
double basis,
DoubleBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceEntriesToDoubleTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public long reduceEntriesToLong(long parallelismThreshold,
ToLongFunction<Map.Entry<K,V>> transformer,
long basis,
LongBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceEntriesToLongTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public int reduceEntriesToInt(long parallelismThreshold,
ToIntFunction<Map.Entry<K,V>> transformer,
int basis,
IntBinaryOperator reducer) {
if (transformer == null || reducer == null)
throw new NullPointerException();
return new MapReduceEntriesToIntTask<K,V>
(null, batchFor(parallelismThreshold), 0, 0, table,
null, transformer, basis, reducer).invoke();
}
/* ----------------Views -------------- */
/**
* Base class for views.
*/
abstract static class CollectionView<K,V,E>
implements Collection<E>, java.io.Serializable {
private static final long serialVersionUID = 7249069246763182397L;
final ConcurrentHashMap<K,V> map;
CollectionView(ConcurrentHashMap<K,V> map) { this.map = map; }
/**
* Returns the map backing this view.
*
* @return the map backing this view
*/
public ConcurrentHashMap<K,V> getMap() { return map; }
/**
* Removes all of the elements from this view, by removing all
* the mappings from the map backing this view.
*/
public final void clear() { map.clear(); }
public final int size() { return map.size(); }
public final boolean isEmpty() { return map.isEmpty(); }
// implementations below rely on concrete classes supplying these
// abstract methods
/**
* Returns a "weakly consistent" iterator that will never
* throw {@link ConcurrentModificationException}, and
* guarantees to traverse elements as they existed upon
* construction of the iterator, and may (but is not
* guaranteed to) reflect any modifications subsequent to
* construction.
*/
public abstract Iterator<E> iterator();
public abstract boolean contains(Object o);
public abstract boolean remove(Object o);
private static final String oomeMsg = "Required array size too large";
public final Object[] toArray() {
long sz = map.mappingCount();
if (sz > MAX_ARRAY_SIZE)
throw new OutOfMemoryError(oomeMsg);
int n = (int)sz;
Object[] r = new Object[n];
int i = 0;
for (E e : this) {
if (i == n) {
if (n >= MAX_ARRAY_SIZE)
throw new OutOfMemoryError(oomeMsg);
if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
n = MAX_ARRAY_SIZE;
else
n += (n >>> 1) + 1;
r = Arrays.copyOf(r, n);
}
r[i++] = e;
}
return (i == n) ? r : Arrays.copyOf(r, i);
}
public final <T> T[] toArray(T[] a) {
long sz = map.mappingCount();
if (sz > MAX_ARRAY_SIZE)
throw new OutOfMemoryError(oomeMsg);
int m = (int)sz;
T[] r = (a.length >= m) ? a :
(T[])java.lang.reflect.Array
.newInstance(a.getClass().getComponentType(), m);
int n = r.length;
int i = 0;
for (E e : this) {
if (i == n) {
if (n >= MAX_ARRAY_SIZE)
throw new OutOfMemoryError(oomeMsg);
if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
n = MAX_ARRAY_SIZE;
else
n += (n >>> 1) + 1;
r = Arrays.copyOf(r, n);
}
r[i++] = (T)e;
}
if (a == r && i < n) {
r[i] = null; // null-terminate
return r;
}
return (i == n) ? r : Arrays.copyOf(r, i);
}
/**
* Returns a string representation of this collection.
* The string representation consists of the string representations
* of the collection's elements in the order they are returned by
* its iterator, enclosed in square brackets ({@code "[]"}).
* Adjacent elements are separated by the characters {@code ", "}
* (comma and space). Elements are converted to strings as by
* {@link String#valueOf(Object)}.
*
* @return a string representation of this collection
*/
public final String toString() {
StringBuilder sb = new StringBuilder();
sb.append('[');
Iterator<E> it = iterator();
if (it.hasNext()) {
for (;;) {
Object e = it.next();
sb.append(e == this ? "(this Collection)" : e);
if (!it.hasNext())
break;
sb.append(',').append(' ');
}
}
return sb.append(']').toString();
}
public final boolean containsAll(Collection<?> c) {
if (c != this) {
for (Object e : c) {
if (e == null || !contains(e))
return false;
}
}
return true;
}
public final boolean removeAll(Collection<?> c) {
boolean modified = false;
for (Iterator<E> it = iterator(); it.hasNext();) {
if (c.contains(it.next())) {
it.remove();
modified = true;
}
}
return modified;
}
public final boolean retainAll(Collection<?> c) {
boolean modified = false;
for (Iterator<E> it = iterator(); it.hasNext();) {
if (!c.contains(it.next())) {
it.remove();
modified = true;
}
}
return modified;
}
}
/**
* A view of a ConcurrentHashMap as a {@link Set} of keys, in
* which additions may optionally be enabled by mapping to a
* common value. This class cannot be directly instantiated.
* See {@link #keySet() keySet()},
* {@link #keySet(Object) keySet(V)},
* {@link #newKeySet() newKeySet()},
* {@link #newKeySet(int) newKeySet(int)}.
* @since 1.8
*/
public static class KeySetView<K,V> extends CollectionView<K,V,K>
implements Set<K>, java.io.Serializable {
private static final long serialVersionUID = 7249069246763182397L;
private final V value;
KeySetView(ConcurrentHashMap<K,V> map, V value) { // non-public
super(map);
this.value = value;
}
/**
* Returns the default mapped value for additions,
* or {@code null} if additions are not supported.
*
* @return the default mapped value for additions, or {@code null}
* if not supported
*/
public V getMappedValue() { return value; }
/**
* {@inheritDoc}
* @throws NullPointerException if the specified key is null
*/
public boolean contains(Object o) { return map.containsKey(o); }
/**
* Removes the key from this map view, by removing the key (and its
* corresponding value) from the backing map. This method does
* nothing if the key is not in the map.
*
* @param o the key to be removed from the backing map
* @return {@code true} if the backing map contained the specified key
* @throws NullPointerException if the specified key is null
*/
public boolean remove(Object o) { return map.remove(o) != null; }
/**
* @return an iterator over the keys of the backing map
*/
public Iterator<K> iterator() {
Node<K,V>[] t;
ConcurrentHashMap<K,V> m = map;
int f = (t = m.table) == null ? 0 : t.length;
return new KeyIterator<K,V>(t, f, 0, f, m);
}
/**
* Adds the specified key to this set view by mapping the key to
* the default mapped value in the backing map, if defined.
*
* @param e key to be added
* @return {@code true} if this set changed as a result of the call
* @throws NullPointerException if the specified key is null
* @throws UnsupportedOperationException if no default mapped value
* for additions was provided
*/
public boolean add(K e) {
V v;
if ((v = value) == null)
throw new UnsupportedOperationException();
return map.internalPut(e, v, true) == null;
}
/**
* Adds all of the elements in the specified collection to this set,
* as if by calling {@link #add} on each one.
*
* @param c the elements to be inserted into this set
* @return {@code true} if this set changed as a result of the call
* @throws NullPointerException if the collection or any of its
* elements are {@code null}
* @throws UnsupportedOperationException if no default mapped value
* for additions was provided
*/
public boolean addAll(Collection<? extends K> c) {
boolean added = false;
V v;
if ((v = value) == null)
throw new UnsupportedOperationException();
for (K e : c) {
if (map.internalPut(e, v, true) == null)
added = true;
}
return added;
}
public int hashCode() {
int h = 0;
for (K e : this)
h += e.hashCode();
return h;
}
public boolean equals(Object o) {
Set<?> c;
return ((o instanceof Set) &&
((c = (Set<?>)o) == this ||
(containsAll(c) && c.containsAll(this))));
}
public Spliterator<K> spliterator() {
Node<K,V>[] t;
ConcurrentHashMap<K,V> m = map;
long n = m.sumCount();
int f = (t = m.table) == null ? 0 : t.length;
return new KeySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
}
public void forEach(Consumer<? super K> action) {
if (action == null) throw new NullPointerException();
Node<K,V>[] t;
if ((t = map.table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; )
action.accept((K)p.key);
}
}
}
/**
* A view of a ConcurrentHashMap as a {@link Collection} of
* values, in which additions are disabled. This class cannot be
* directly instantiated. See {@link #values()}.
*/
static final class ValuesView<K,V> extends CollectionView<K,V,V>
implements Collection<V>, java.io.Serializable {
private static final long serialVersionUID = 2249069246763182397L;
ValuesView(ConcurrentHashMap<K,V> map) { super(map); }
public final boolean contains(Object o) {
return map.containsValue(o);
}
public final boolean remove(Object o) {
if (o != null) {
for (Iterator<V> it = iterator(); it.hasNext();) {
if (o.equals(it.next())) {
it.remove();
return true;
}
}
}
return false;
}
public final Iterator<V> iterator() {
ConcurrentHashMap<K,V> m = map;
Node<K,V>[] t;
int f = (t = m.table) == null ? 0 : t.length;
return new ValueIterator<K,V>(t, f, 0, f, m);
}
public final boolean add(V e) {
throw new UnsupportedOperationException();
}
public final boolean addAll(Collection<? extends V> c) {
throw new UnsupportedOperationException();
}
public Spliterator<V> spliterator() {
Node<K,V>[] t;
ConcurrentHashMap<K,V> m = map;
long n = m.sumCount();
int f = (t = m.table) == null ? 0 : t.length;
return new ValueSpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
}
public void forEach(Consumer<? super V> action) {
if (action == null) throw new NullPointerException();
Node<K,V>[] t;
if ((t = map.table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; )
action.accept(p.val);
}
}
}
/**
* A view of a ConcurrentHashMap as a {@link Set} of (key, value)
* entries. This class cannot be directly instantiated. See
* {@link #entrySet()}.
*/
static final class EntrySetView<K,V> extends CollectionView<K,V,Map.Entry<K,V>>
implements Set<Map.Entry<K,V>>, java.io.Serializable {
private static final long serialVersionUID = 2249069246763182397L;
EntrySetView(ConcurrentHashMap<K,V> map) { super(map); }
public boolean contains(Object o) {
Object k, v, r; Map.Entry<?,?> e;
return ((o instanceof Map.Entry) &&
(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
(r = map.get(k)) != null &&
(v = e.getValue()) != null &&
(v == r || v.equals(r)));
}
public boolean remove(Object o) {
Object k, v; Map.Entry<?,?> e;
return ((o instanceof Map.Entry) &&
(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
(v = e.getValue()) != null &&
map.remove(k, v));
}
/**
* @return an iterator over the entries of the backing map
*/
public Iterator<Map.Entry<K,V>> iterator() {
ConcurrentHashMap<K,V> m = map;
Node<K,V>[] t;
int f = (t = m.table) == null ? 0 : t.length;
return new EntryIterator<K,V>(t, f, 0, f, m);
}
public boolean add(Entry<K,V> e) {
return map.internalPut(e.getKey(), e.getValue(), false) == null;
}
public boolean addAll(Collection<? extends Entry<K,V>> c) {
boolean added = false;
for (Entry<K,V> e : c) {
if (add(e))
added = true;
}
return added;
}
public final int hashCode() {
int h = 0;
Node<K,V>[] t;
if ((t = map.table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; ) {
h += p.hashCode();
}
}
return h;
}
public final boolean equals(Object o) {
Set<?> c;
return ((o instanceof Set) &&
((c = (Set<?>)o) == this ||
(containsAll(c) && c.containsAll(this))));
}
public Spliterator<Map.Entry<K,V>> spliterator() {
Node<K,V>[] t;
ConcurrentHashMap<K,V> m = map;
long n = m.sumCount();
int f = (t = m.table) == null ? 0 : t.length;
return new EntrySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n, m);
}
public void forEach(Consumer<? super Map.Entry<K,V>> action) {
if (action == null) throw new NullPointerException();
Node<K,V>[] t;
if ((t = map.table) != null) {
Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
for (Node<K,V> p; (p = it.advance()) != null; )
action.accept(new MapEntry<K,V>((K)p.key, p.val, map));
}
}
}
// -------------------------------------------------------
/**
* Base class for bulk tasks. Repeats some fields and code from
* class Traverser, because we need to subclass CountedCompleter.
*/
abstract static class BulkTask<K,V,R> extends CountedCompleter<R> {
Node<K,V>[] tab; // same as Traverser
Node<K,V> next;
int index;
int baseIndex;
int baseLimit;
final int baseSize;
int batch; // split control
BulkTask(BulkTask<K,V,?> par, int b, int i, int f, Node<K,V>[] t) {
super(par);
this.batch = b;
this.index = this.baseIndex = i;
if ((this.tab = t) == null)
this.baseSize = this.baseLimit = 0;
else if (par == null)
this.baseSize = this.baseLimit = t.length;
else {
this.baseLimit = f;
this.baseSize = par.baseSize;
}
}
/**
* Same as Traverser version
*/
final Node<K,V> advance() {
Node<K,V> e;
if ((e = next) != null)
e = e.next;
for (;;) {
Node<K,V>[] t; int i, n; Object ek;
if (e != null)
return next = e;
if (baseIndex >= baseLimit || (t = tab) == null ||
(n = t.length) <= (i = index) || i < 0)
return next = null;
if ((e = tabAt(t, index)) != null && e.hash < 0) {
if ((ek = e.key) instanceof TreeBin)
e = ((TreeBin<K,V>)ek).first;
else {
tab = (Node<K,V>[])ek;
e = null;
continue;
}
}
if ((index += baseSize) >= n)
index = ++baseIndex;
}
}
}
/*
* Task classes. Coded in a regular but ugly format/style to
* simplify checks that each variant differs in the right way from
* others. The null screenings exist because compilers cannot tell
* that we've already null-checked task arguments, so we force
* simplest hoisted bypass to help avoid convoluted traps.
*/
static final class ForEachKeyTask<K,V>
extends BulkTask<K,V,Void> {
final Consumer<? super K> action;
ForEachKeyTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Consumer<? super K> action) {
super(p, b, i, f, t);
this.action = action;
}
public final void compute() {
final Consumer<? super K> action;
if ((action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachKeyTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
action).fork();
}
for (Node<K,V> p; (p = advance()) != null;)
action.accept((K)p.key);
propagateCompletion();
}
}
}
static final class ForEachValueTask<K,V>
extends BulkTask<K,V,Void> {
final Consumer<? super V> action;
ForEachValueTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Consumer<? super V> action) {
super(p, b, i, f, t);
this.action = action;
}
public final void compute() {
final Consumer<? super V> action;
if ((action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachValueTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
action).fork();
}
for (Node<K,V> p; (p = advance()) != null;)
action.accept(p.val);
propagateCompletion();
}
}
}
static final class ForEachEntryTask<K,V>
extends BulkTask<K,V,Void> {
final Consumer<? super Entry<K,V>> action;
ForEachEntryTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Consumer<? super Entry<K,V>> action) {
super(p, b, i, f, t);
this.action = action;
}
public final void compute() {
final Consumer<? super Entry<K,V>> action;
if ((action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachEntryTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
action).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
action.accept(p);
propagateCompletion();
}
}
}
static final class ForEachMappingTask<K,V>
extends BulkTask<K,V,Void> {
final BiConsumer<? super K, ? super V> action;
ForEachMappingTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
BiConsumer<? super K,? super V> action) {
super(p, b, i, f, t);
this.action = action;
}
public final void compute() {
final BiConsumer<? super K, ? super V> action;
if ((action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachMappingTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
action).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
action.accept((K)p.key, p.val);
propagateCompletion();
}
}
}
static final class ForEachTransformedKeyTask<K,V,U>
extends BulkTask<K,V,Void> {
final Function<? super K, ? extends U> transformer;
final Consumer<? super U> action;
ForEachTransformedKeyTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Function<? super K, ? extends U> transformer, Consumer<? super U> action) {
super(p, b, i, f, t);
this.transformer = transformer; this.action = action;
}
public final void compute() {
final Function<? super K, ? extends U> transformer;
final Consumer<? super U> action;
if ((transformer = this.transformer) != null &&
(action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachTransformedKeyTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
transformer, action).fork();
}
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply((K)p.key)) != null)
action.accept(u);
}
propagateCompletion();
}
}
}
static final class ForEachTransformedValueTask<K,V,U>
extends BulkTask<K,V,Void> {
final Function<? super V, ? extends U> transformer;
final Consumer<? super U> action;
ForEachTransformedValueTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Function<? super V, ? extends U> transformer, Consumer<? super U> action) {
super(p, b, i, f, t);
this.transformer = transformer; this.action = action;
}
public final void compute() {
final Function<? super V, ? extends U> transformer;
final Consumer<? super U> action;
if ((transformer = this.transformer) != null &&
(action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachTransformedValueTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
transformer, action).fork();
}
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply(p.val)) != null)
action.accept(u);
}
propagateCompletion();
}
}
}
static final class ForEachTransformedEntryTask<K,V,U>
extends BulkTask<K,V,Void> {
final Function<Map.Entry<K,V>, ? extends U> transformer;
final Consumer<? super U> action;
ForEachTransformedEntryTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Function<Map.Entry<K,V>, ? extends U> transformer, Consumer<? super U> action) {
super(p, b, i, f, t);
this.transformer = transformer; this.action = action;
}
public final void compute() {
final Function<Map.Entry<K,V>, ? extends U> transformer;
final Consumer<? super U> action;
if ((transformer = this.transformer) != null &&
(action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachTransformedEntryTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
transformer, action).fork();
}
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply(p)) != null)
action.accept(u);
}
propagateCompletion();
}
}
}
static final class ForEachTransformedMappingTask<K,V,U>
extends BulkTask<K,V,Void> {
final BiFunction<? super K, ? super V, ? extends U> transformer;
final Consumer<? super U> action;
ForEachTransformedMappingTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
BiFunction<? super K, ? super V, ? extends U> transformer,
Consumer<? super U> action) {
super(p, b, i, f, t);
this.transformer = transformer; this.action = action;
}
public final void compute() {
final BiFunction<? super K, ? super V, ? extends U> transformer;
final Consumer<? super U> action;
if ((transformer = this.transformer) != null &&
(action = this.action) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
new ForEachTransformedMappingTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
transformer, action).fork();
}
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply((K)p.key, p.val)) != null)
action.accept(u);
}
propagateCompletion();
}
}
}
static final class SearchKeysTask<K,V,U>
extends BulkTask<K,V,U> {
final Function<? super K, ? extends U> searchFunction;
final AtomicReference<U> result;
SearchKeysTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Function<? super K, ? extends U> searchFunction,
AtomicReference<U> result) {
super(p, b, i, f, t);
this.searchFunction = searchFunction; this.result = result;
}
public final U getRawResult() { return result.get(); }
public final void compute() {
final Function<? super K, ? extends U> searchFunction;
final AtomicReference<U> result;
if ((searchFunction = this.searchFunction) != null &&
(result = this.result) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
if (result.get() != null)
return;
addToPendingCount(1);
new SearchKeysTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
searchFunction, result).fork();
}
while (result.get() == null) {
U u;
Node<K,V> p;
if ((p = advance()) == null) {
propagateCompletion();
break;
}
if ((u = searchFunction.apply((K)p.key)) != null) {
if (result.compareAndSet(null, u))
quietlyCompleteRoot();
break;
}
}
}
}
}
static final class SearchValuesTask<K,V,U>
extends BulkTask<K,V,U> {
final Function<? super V, ? extends U> searchFunction;
final AtomicReference<U> result;
SearchValuesTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Function<? super V, ? extends U> searchFunction,
AtomicReference<U> result) {
super(p, b, i, f, t);
this.searchFunction = searchFunction; this.result = result;
}
public final U getRawResult() { return result.get(); }
public final void compute() {
final Function<? super V, ? extends U> searchFunction;
final AtomicReference<U> result;
if ((searchFunction = this.searchFunction) != null &&
(result = this.result) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
if (result.get() != null)
return;
addToPendingCount(1);
new SearchValuesTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
searchFunction, result).fork();
}
while (result.get() == null) {
U u;
Node<K,V> p;
if ((p = advance()) == null) {
propagateCompletion();
break;
}
if ((u = searchFunction.apply(p.val)) != null) {
if (result.compareAndSet(null, u))
quietlyCompleteRoot();
break;
}
}
}
}
}
static final class SearchEntriesTask<K,V,U>
extends BulkTask<K,V,U> {
final Function<Entry<K,V>, ? extends U> searchFunction;
final AtomicReference<U> result;
SearchEntriesTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
Function<Entry<K,V>, ? extends U> searchFunction,
AtomicReference<U> result) {
super(p, b, i, f, t);
this.searchFunction = searchFunction; this.result = result;
}
public final U getRawResult() { return result.get(); }
public final void compute() {
final Function<Entry<K,V>, ? extends U> searchFunction;
final AtomicReference<U> result;
if ((searchFunction = this.searchFunction) != null &&
(result = this.result) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
if (result.get() != null)
return;
addToPendingCount(1);
new SearchEntriesTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
searchFunction, result).fork();
}
while (result.get() == null) {
U u;
Node<K,V> p;
if ((p = advance()) == null) {
propagateCompletion();
break;
}
if ((u = searchFunction.apply(p)) != null) {
if (result.compareAndSet(null, u))
quietlyCompleteRoot();
return;
}
}
}
}
}
static final class SearchMappingsTask<K,V,U>
extends BulkTask<K,V,U> {
final BiFunction<? super K, ? super V, ? extends U> searchFunction;
final AtomicReference<U> result;
SearchMappingsTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
BiFunction<? super K, ? super V, ? extends U> searchFunction,
AtomicReference<U> result) {
super(p, b, i, f, t);
this.searchFunction = searchFunction; this.result = result;
}
public final U getRawResult() { return result.get(); }
public final void compute() {
final BiFunction<? super K, ? super V, ? extends U> searchFunction;
final AtomicReference<U> result;
if ((searchFunction = this.searchFunction) != null &&
(result = this.result) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
if (result.get() != null)
return;
addToPendingCount(1);
new SearchMappingsTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
searchFunction, result).fork();
}
while (result.get() == null) {
U u;
Node<K,V> p;
if ((p = advance()) == null) {
propagateCompletion();
break;
}
if ((u = searchFunction.apply((K)p.key, p.val)) != null) {
if (result.compareAndSet(null, u))
quietlyCompleteRoot();
break;
}
}
}
}
}
static final class ReduceKeysTask<K,V>
extends BulkTask<K,V,K> {
final BiFunction<? super K, ? super K, ? extends K> reducer;
K result;
ReduceKeysTask<K,V> rights, nextRight;
ReduceKeysTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
ReduceKeysTask<K,V> nextRight,
BiFunction<? super K, ? super K, ? extends K> reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.reducer = reducer;
}
public final K getRawResult() { return result; }
public final void compute() {
final BiFunction<? super K, ? super K, ? extends K> reducer;
if ((reducer = this.reducer) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new ReduceKeysTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, reducer)).fork();
}
K r = null;
for (Node<K,V> p; (p = advance()) != null; ) {
K u = (K)p.key;
r = (r == null) ? u : u == null ? r : reducer.apply(r, u);
}
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
ReduceKeysTask<K,V>
t = (ReduceKeysTask<K,V>)c,
s = t.rights;
while (s != null) {
K tr, sr;
if ((sr = s.result) != null)
t.result = (((tr = t.result) == null) ? sr :
reducer.apply(tr, sr));
s = t.rights = s.nextRight;
}
}
}
}
}
static final class ReduceValuesTask<K,V>
extends BulkTask<K,V,V> {
final BiFunction<? super V, ? super V, ? extends V> reducer;
V result;
ReduceValuesTask<K,V> rights, nextRight;
ReduceValuesTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
ReduceValuesTask<K,V> nextRight,
BiFunction<? super V, ? super V, ? extends V> reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.reducer = reducer;
}
public final V getRawResult() { return result; }
public final void compute() {
final BiFunction<? super V, ? super V, ? extends V> reducer;
if ((reducer = this.reducer) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new ReduceValuesTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, reducer)).fork();
}
V r = null;
for (Node<K,V> p; (p = advance()) != null; ) {
V v = p.val;
r = (r == null) ? v : reducer.apply(r, v);
}
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
ReduceValuesTask<K,V>
t = (ReduceValuesTask<K,V>)c,
s = t.rights;
while (s != null) {
V tr, sr;
if ((sr = s.result) != null)
t.result = (((tr = t.result) == null) ? sr :
reducer.apply(tr, sr));
s = t.rights = s.nextRight;
}
}
}
}
}
static final class ReduceEntriesTask<K,V>
extends BulkTask<K,V,Map.Entry<K,V>> {
final BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
Map.Entry<K,V> result;
ReduceEntriesTask<K,V> rights, nextRight;
ReduceEntriesTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
ReduceEntriesTask<K,V> nextRight,
BiFunction<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.reducer = reducer;
}
public final Map.Entry<K,V> getRawResult() { return result; }
public final void compute() {
final BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
if ((reducer = this.reducer) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new ReduceEntriesTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, reducer)).fork();
}
Map.Entry<K,V> r = null;
for (Node<K,V> p; (p = advance()) != null; )
r = (r == null) ? p : reducer.apply(r, p);
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
ReduceEntriesTask<K,V>
t = (ReduceEntriesTask<K,V>)c,
s = t.rights;
while (s != null) {
Map.Entry<K,V> tr, sr;
if ((sr = s.result) != null)
t.result = (((tr = t.result) == null) ? sr :
reducer.apply(tr, sr));
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceKeysTask<K,V,U>
extends BulkTask<K,V,U> {
final Function<? super K, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
U result;
MapReduceKeysTask<K,V,U> rights, nextRight;
MapReduceKeysTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceKeysTask<K,V,U> nextRight,
Function<? super K, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.reducer = reducer;
}
public final U getRawResult() { return result; }
public final void compute() {
final Function<? super K, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceKeysTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, reducer)).fork();
}
U r = null;
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply((K)p.key)) != null)
r = (r == null) ? u : reducer.apply(r, u);
}
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceKeysTask<K,V,U>
t = (MapReduceKeysTask<K,V,U>)c,
s = t.rights;
while (s != null) {
U tr, sr;
if ((sr = s.result) != null)
t.result = (((tr = t.result) == null) ? sr :
reducer.apply(tr, sr));
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceValuesTask<K,V,U>
extends BulkTask<K,V,U> {
final Function<? super V, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
U result;
MapReduceValuesTask<K,V,U> rights, nextRight;
MapReduceValuesTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceValuesTask<K,V,U> nextRight,
Function<? super V, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.reducer = reducer;
}
public final U getRawResult() { return result; }
public final void compute() {
final Function<? super V, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceValuesTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, reducer)).fork();
}
U r = null;
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply(p.val)) != null)
r = (r == null) ? u : reducer.apply(r, u);
}
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceValuesTask<K,V,U>
t = (MapReduceValuesTask<K,V,U>)c,
s = t.rights;
while (s != null) {
U tr, sr;
if ((sr = s.result) != null)
t.result = (((tr = t.result) == null) ? sr :
reducer.apply(tr, sr));
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceEntriesTask<K,V,U>
extends BulkTask<K,V,U> {
final Function<Map.Entry<K,V>, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
U result;
MapReduceEntriesTask<K,V,U> rights, nextRight;
MapReduceEntriesTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceEntriesTask<K,V,U> nextRight,
Function<Map.Entry<K,V>, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.reducer = reducer;
}
public final U getRawResult() { return result; }
public final void compute() {
final Function<Map.Entry<K,V>, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceEntriesTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, reducer)).fork();
}
U r = null;
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply(p)) != null)
r = (r == null) ? u : reducer.apply(r, u);
}
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceEntriesTask<K,V,U>
t = (MapReduceEntriesTask<K,V,U>)c,
s = t.rights;
while (s != null) {
U tr, sr;
if ((sr = s.result) != null)
t.result = (((tr = t.result) == null) ? sr :
reducer.apply(tr, sr));
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceMappingsTask<K,V,U>
extends BulkTask<K,V,U> {
final BiFunction<? super K, ? super V, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
U result;
MapReduceMappingsTask<K,V,U> rights, nextRight;
MapReduceMappingsTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceMappingsTask<K,V,U> nextRight,
BiFunction<? super K, ? super V, ? extends U> transformer,
BiFunction<? super U, ? super U, ? extends U> reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.reducer = reducer;
}
public final U getRawResult() { return result; }
public final void compute() {
final BiFunction<? super K, ? super V, ? extends U> transformer;
final BiFunction<? super U, ? super U, ? extends U> reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceMappingsTask<K,V,U>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, reducer)).fork();
}
U r = null;
for (Node<K,V> p; (p = advance()) != null; ) {
U u;
if ((u = transformer.apply((K)p.key, p.val)) != null)
r = (r == null) ? u : reducer.apply(r, u);
}
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceMappingsTask<K,V,U>
t = (MapReduceMappingsTask<K,V,U>)c,
s = t.rights;
while (s != null) {
U tr, sr;
if ((sr = s.result) != null)
t.result = (((tr = t.result) == null) ? sr :
reducer.apply(tr, sr));
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceKeysToDoubleTask<K,V>
extends BulkTask<K,V,Double> {
final ToDoubleFunction<? super K> transformer;
final DoubleBinaryOperator reducer;
final double basis;
double result;
MapReduceKeysToDoubleTask<K,V> rights, nextRight;
MapReduceKeysToDoubleTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceKeysToDoubleTask<K,V> nextRight,
ToDoubleFunction<? super K> transformer,
double basis,
DoubleBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Double getRawResult() { return result; }
public final void compute() {
final ToDoubleFunction<? super K> transformer;
final DoubleBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
double r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceKeysToDoubleTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsDouble(r, transformer.applyAsDouble((K)p.key));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceKeysToDoubleTask<K,V>
t = (MapReduceKeysToDoubleTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsDouble(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceValuesToDoubleTask<K,V>
extends BulkTask<K,V,Double> {
final ToDoubleFunction<? super V> transformer;
final DoubleBinaryOperator reducer;
final double basis;
double result;
MapReduceValuesToDoubleTask<K,V> rights, nextRight;
MapReduceValuesToDoubleTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceValuesToDoubleTask<K,V> nextRight,
ToDoubleFunction<? super V> transformer,
double basis,
DoubleBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Double getRawResult() { return result; }
public final void compute() {
final ToDoubleFunction<? super V> transformer;
final DoubleBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
double r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceValuesToDoubleTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsDouble(r, transformer.applyAsDouble(p.val));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceValuesToDoubleTask<K,V>
t = (MapReduceValuesToDoubleTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsDouble(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceEntriesToDoubleTask<K,V>
extends BulkTask<K,V,Double> {
final ToDoubleFunction<Map.Entry<K,V>> transformer;
final DoubleBinaryOperator reducer;
final double basis;
double result;
MapReduceEntriesToDoubleTask<K,V> rights, nextRight;
MapReduceEntriesToDoubleTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceEntriesToDoubleTask<K,V> nextRight,
ToDoubleFunction<Map.Entry<K,V>> transformer,
double basis,
DoubleBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Double getRawResult() { return result; }
public final void compute() {
final ToDoubleFunction<Map.Entry<K,V>> transformer;
final DoubleBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
double r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceEntriesToDoubleTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsDouble(r, transformer.applyAsDouble(p));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceEntriesToDoubleTask<K,V>
t = (MapReduceEntriesToDoubleTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsDouble(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceMappingsToDoubleTask<K,V>
extends BulkTask<K,V,Double> {
final ToDoubleBiFunction<? super K, ? super V> transformer;
final DoubleBinaryOperator reducer;
final double basis;
double result;
MapReduceMappingsToDoubleTask<K,V> rights, nextRight;
MapReduceMappingsToDoubleTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceMappingsToDoubleTask<K,V> nextRight,
ToDoubleBiFunction<? super K, ? super V> transformer,
double basis,
DoubleBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Double getRawResult() { return result; }
public final void compute() {
final ToDoubleBiFunction<? super K, ? super V> transformer;
final DoubleBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
double r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceMappingsToDoubleTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsDouble(r, transformer.applyAsDouble((K)p.key, p.val));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceMappingsToDoubleTask<K,V>
t = (MapReduceMappingsToDoubleTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsDouble(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceKeysToLongTask<K,V>
extends BulkTask<K,V,Long> {
final ToLongFunction<? super K> transformer;
final LongBinaryOperator reducer;
final long basis;
long result;
MapReduceKeysToLongTask<K,V> rights, nextRight;
MapReduceKeysToLongTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceKeysToLongTask<K,V> nextRight,
ToLongFunction<? super K> transformer,
long basis,
LongBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Long getRawResult() { return result; }
public final void compute() {
final ToLongFunction<? super K> transformer;
final LongBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
long r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceKeysToLongTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsLong(r, transformer.applyAsLong((K)p.key));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceKeysToLongTask<K,V>
t = (MapReduceKeysToLongTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsLong(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceValuesToLongTask<K,V>
extends BulkTask<K,V,Long> {
final ToLongFunction<? super V> transformer;
final LongBinaryOperator reducer;
final long basis;
long result;
MapReduceValuesToLongTask<K,V> rights, nextRight;
MapReduceValuesToLongTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceValuesToLongTask<K,V> nextRight,
ToLongFunction<? super V> transformer,
long basis,
LongBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Long getRawResult() { return result; }
public final void compute() {
final ToLongFunction<? super V> transformer;
final LongBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
long r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceValuesToLongTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsLong(r, transformer.applyAsLong(p.val));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceValuesToLongTask<K,V>
t = (MapReduceValuesToLongTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsLong(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceEntriesToLongTask<K,V>
extends BulkTask<K,V,Long> {
final ToLongFunction<Map.Entry<K,V>> transformer;
final LongBinaryOperator reducer;
final long basis;
long result;
MapReduceEntriesToLongTask<K,V> rights, nextRight;
MapReduceEntriesToLongTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceEntriesToLongTask<K,V> nextRight,
ToLongFunction<Map.Entry<K,V>> transformer,
long basis,
LongBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Long getRawResult() { return result; }
public final void compute() {
final ToLongFunction<Map.Entry<K,V>> transformer;
final LongBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
long r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceEntriesToLongTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsLong(r, transformer.applyAsLong(p));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceEntriesToLongTask<K,V>
t = (MapReduceEntriesToLongTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsLong(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceMappingsToLongTask<K,V>
extends BulkTask<K,V,Long> {
final ToLongBiFunction<? super K, ? super V> transformer;
final LongBinaryOperator reducer;
final long basis;
long result;
MapReduceMappingsToLongTask<K,V> rights, nextRight;
MapReduceMappingsToLongTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceMappingsToLongTask<K,V> nextRight,
ToLongBiFunction<? super K, ? super V> transformer,
long basis,
LongBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Long getRawResult() { return result; }
public final void compute() {
final ToLongBiFunction<? super K, ? super V> transformer;
final LongBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
long r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceMappingsToLongTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsLong(r, transformer.applyAsLong((K)p.key, p.val));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceMappingsToLongTask<K,V>
t = (MapReduceMappingsToLongTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsLong(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceKeysToIntTask<K,V>
extends BulkTask<K,V,Integer> {
final ToIntFunction<? super K> transformer;
final IntBinaryOperator reducer;
final int basis;
int result;
MapReduceKeysToIntTask<K,V> rights, nextRight;
MapReduceKeysToIntTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceKeysToIntTask<K,V> nextRight,
ToIntFunction<? super K> transformer,
int basis,
IntBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Integer getRawResult() { return result; }
public final void compute() {
final ToIntFunction<? super K> transformer;
final IntBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
int r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceKeysToIntTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsInt(r, transformer.applyAsInt((K)p.key));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceKeysToIntTask<K,V>
t = (MapReduceKeysToIntTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsInt(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceValuesToIntTask<K,V>
extends BulkTask<K,V,Integer> {
final ToIntFunction<? super V> transformer;
final IntBinaryOperator reducer;
final int basis;
int result;
MapReduceValuesToIntTask<K,V> rights, nextRight;
MapReduceValuesToIntTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceValuesToIntTask<K,V> nextRight,
ToIntFunction<? super V> transformer,
int basis,
IntBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Integer getRawResult() { return result; }
public final void compute() {
final ToIntFunction<? super V> transformer;
final IntBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
int r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceValuesToIntTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsInt(r, transformer.applyAsInt(p.val));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceValuesToIntTask<K,V>
t = (MapReduceValuesToIntTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsInt(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceEntriesToIntTask<K,V>
extends BulkTask<K,V,Integer> {
final ToIntFunction<Map.Entry<K,V>> transformer;
final IntBinaryOperator reducer;
final int basis;
int result;
MapReduceEntriesToIntTask<K,V> rights, nextRight;
MapReduceEntriesToIntTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceEntriesToIntTask<K,V> nextRight,
ToIntFunction<Map.Entry<K,V>> transformer,
int basis,
IntBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Integer getRawResult() { return result; }
public final void compute() {
final ToIntFunction<Map.Entry<K,V>> transformer;
final IntBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
int r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceEntriesToIntTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsInt(r, transformer.applyAsInt(p));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceEntriesToIntTask<K,V>
t = (MapReduceEntriesToIntTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsInt(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
static final class MapReduceMappingsToIntTask<K,V>
extends BulkTask<K,V,Integer> {
final ToIntBiFunction<? super K, ? super V> transformer;
final IntBinaryOperator reducer;
final int basis;
int result;
MapReduceMappingsToIntTask<K,V> rights, nextRight;
MapReduceMappingsToIntTask
(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
MapReduceMappingsToIntTask<K,V> nextRight,
ToIntBiFunction<? super K, ? super V> transformer,
int basis,
IntBinaryOperator reducer) {
super(p, b, i, f, t); this.nextRight = nextRight;
this.transformer = transformer;
this.basis = basis; this.reducer = reducer;
}
public final Integer getRawResult() { return result; }
public final void compute() {
final ToIntBiFunction<? super K, ? super V> transformer;
final IntBinaryOperator reducer;
if ((transformer = this.transformer) != null &&
(reducer = this.reducer) != null) {
int r = this.basis;
for (int i = baseIndex, f, h; batch > 0 &&
(h = ((f = baseLimit) + i) >>> 1) > i;) {
addToPendingCount(1);
(rights = new MapReduceMappingsToIntTask<K,V>
(this, batch >>>= 1, baseLimit = h, f, tab,
rights, transformer, r, reducer)).fork();
}
for (Node<K,V> p; (p = advance()) != null; )
r = reducer.applyAsInt(r, transformer.applyAsInt((K)p.key, p.val));
result = r;
CountedCompleter<?> c;
for (c = firstComplete(); c != null; c = c.nextComplete()) {
MapReduceMappingsToIntTask<K,V>
t = (MapReduceMappingsToIntTask<K,V>)c,
s = t.rights;
while (s != null) {
t.result = reducer.applyAsInt(t.result, s.result);
s = t.rights = s.nextRight;
}
}
}
}
}
// Unsafe mechanics
private static final sun.misc.Unsafe U;
private static final long SIZECTL;
private static final long TRANSFERINDEX;
private static final long TRANSFERORIGIN;
private static final long BASECOUNT;
private static final long CELLSBUSY;
private static final long CELLVALUE;
private static final long ABASE;
private static final int ASHIFT;
static {
try {
U = sun.misc.Unsafe.getUnsafe();
Class<?> k = ConcurrentHashMap.class;
SIZECTL = U.objectFieldOffset
(k.getDeclaredField("sizeCtl"));
TRANSFERINDEX = U.objectFieldOffset
(k.getDeclaredField("transferIndex"));
TRANSFERORIGIN = U.objectFieldOffset
(k.getDeclaredField("transferOrigin"));
BASECOUNT = U.objectFieldOffset
(k.getDeclaredField("baseCount"));
CELLSBUSY = U.objectFieldOffset
(k.getDeclaredField("cellsBusy"));
Class<?> ck = Cell.class;
CELLVALUE = U.objectFieldOffset
(ck.getDeclaredField("value"));
Class<?> sc = Node[].class;
ABASE = U.arrayBaseOffset(sc);
int scale = U.arrayIndexScale(sc);
if ((scale & (scale - 1)) != 0)
throw new Error("data type scale not a power of two");
ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
} catch (Exception e) {
throw new Error(e);
}
}
}