--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/util/LinkedHashMap.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,755 @@
+/*
+ * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * 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.
+ */
+
+package java.util;
+
+import java.util.function.Consumer;
+import java.util.function.BiConsumer;
+import java.util.function.BiFunction;
+import java.io.IOException;
+
+/**
+ * <p>Hash table and linked list implementation of the {@code Map} interface,
+ * with predictable iteration order. This implementation differs from
+ * {@code HashMap} in that it maintains a doubly-linked list running through
+ * all of its entries. This linked list defines the iteration ordering,
+ * which is normally the order in which keys were inserted into the map
+ * (<i>insertion-order</i>). Note that insertion order is not affected
+ * if a key is <i>re-inserted</i> into the map. (A key {@code k} is
+ * reinserted into a map {@code m} if {@code m.put(k, v)} is invoked when
+ * {@code m.containsKey(k)} would return {@code true} immediately prior to
+ * the invocation.)
+ *
+ * <p>This implementation spares its clients from the unspecified, generally
+ * chaotic ordering provided by {@link HashMap} (and {@link Hashtable}),
+ * without incurring the increased cost associated with {@link TreeMap}. It
+ * can be used to produce a copy of a map that has the same order as the
+ * original, regardless of the original map's implementation:
+ * <pre>
+ * void foo(Map m) {
+ * Map copy = new LinkedHashMap(m);
+ * ...
+ * }
+ * </pre>
+ * This technique is particularly useful if a module takes a map on input,
+ * copies it, and later returns results whose order is determined by that of
+ * the copy. (Clients generally appreciate having things returned in the same
+ * order they were presented.)
+ *
+ * <p>A special {@link #LinkedHashMap(int,float,boolean) constructor} is
+ * provided to create a linked hash map whose order of iteration is the order
+ * in which its entries were last accessed, from least-recently accessed to
+ * most-recently (<i>access-order</i>). This kind of map is well-suited to
+ * building LRU caches. Invoking the {@code put}, {@code putIfAbsent},
+ * {@code get}, {@code getOrDefault}, {@code compute}, {@code computeIfAbsent},
+ * {@code computeIfPresent}, or {@code merge} methods results
+ * in an access to the corresponding entry (assuming it exists after the
+ * invocation completes). The {@code replace} methods only result in an access
+ * of the entry if the value is replaced. The {@code putAll} method generates one
+ * entry access for each mapping in the specified map, in the order that
+ * key-value mappings are provided by the specified map's entry set iterator.
+ * <i>No other methods generate entry accesses.</i> In particular, operations
+ * on collection-views do <i>not</i> affect the order of iteration of the
+ * backing map.
+ *
+ * <p>The {@link #removeEldestEntry(Map.Entry)} method may be overridden to
+ * impose a policy for removing stale mappings automatically when new mappings
+ * are added to the map.
+ *
+ * <p>This class provides all of the optional {@code Map} operations, and
+ * permits null elements. Like {@code HashMap}, it provides constant-time
+ * performance for the basic operations ({@code add}, {@code contains} and
+ * {@code remove}), assuming the hash function disperses elements
+ * properly among the buckets. Performance is likely to be just slightly
+ * below that of {@code HashMap}, due to the added expense of maintaining the
+ * linked list, with one exception: Iteration over the collection-views
+ * of a {@code LinkedHashMap} requires time proportional to the <i>size</i>
+ * of the map, regardless of its capacity. Iteration over a {@code HashMap}
+ * is likely to be more expensive, requiring time proportional to its
+ * <i>capacity</i>.
+ *
+ * <p>A linked hash map has two parameters that affect its performance:
+ * <i>initial capacity</i> and <i>load factor</i>. They are defined precisely
+ * as for {@code HashMap}. Note, however, that the penalty for choosing an
+ * excessively high value for initial capacity is less severe for this class
+ * than for {@code HashMap}, as iteration times for this class are unaffected
+ * by capacity.
+ *
+ * <p><strong>Note that this implementation is not synchronized.</strong>
+ * If multiple threads access a linked hash map concurrently, and at least
+ * one of the threads modifies the map structurally, it <em>must</em> be
+ * synchronized externally. This is typically accomplished by
+ * synchronizing on some object that naturally encapsulates the map.
+ *
+ * If no such object exists, the map should be "wrapped" using the
+ * {@link Collections#synchronizedMap Collections.synchronizedMap}
+ * method. This is best done at creation time, to prevent accidental
+ * unsynchronized access to the map:<pre>
+ * Map m = Collections.synchronizedMap(new LinkedHashMap(...));</pre>
+ *
+ * A structural modification is any operation that adds or deletes one or more
+ * mappings or, in the case of access-ordered linked hash maps, affects
+ * iteration order. In insertion-ordered linked hash maps, merely changing
+ * the value associated with a key that is already contained in the map is not
+ * a structural modification. <strong>In access-ordered linked hash maps,
+ * merely querying the map with {@code get} is a structural modification.
+ * </strong>)
+ *
+ * <p>The iterators returned by the {@code iterator} method of the collections
+ * returned by all of this class's collection view methods are
+ * <em>fail-fast</em>: if the map is structurally modified at any time after
+ * the iterator is created, in any way except through the iterator's own
+ * {@code remove} method, the iterator will throw a {@link
+ * ConcurrentModificationException}. Thus, in the face of concurrent
+ * modification, the iterator fails quickly and cleanly, rather than risking
+ * arbitrary, non-deterministic behavior at an undetermined time in the future.
+ *
+ * <p>Note that the fail-fast behavior of an iterator cannot be guaranteed
+ * as it is, generally speaking, impossible to make any hard guarantees in the
+ * presence of unsynchronized concurrent modification. Fail-fast iterators
+ * throw {@code ConcurrentModificationException} on a best-effort basis.
+ * Therefore, it would be wrong to write a program that depended on this
+ * exception for its correctness: <i>the fail-fast behavior of iterators
+ * should be used only to detect bugs.</i>
+ *
+ * <p>The spliterators returned by the spliterator method of the collections
+ * returned by all of this class's collection view methods are
+ * <em><a href="Spliterator.html#binding">late-binding</a></em>,
+ * <em>fail-fast</em>, and additionally report {@link Spliterator#ORDERED}.
+ *
+ * <p>This class is a member of the
+ * <a href="{@docRoot}/java/util/package-summary.html#CollectionsFramework">
+ * Java Collections Framework</a>.
+ *
+ * @implNote
+ * The spliterators returned by the spliterator method of the collections
+ * returned by all of this class's collection view methods are created from
+ * the iterators of the corresponding collections.
+ *
+ * @param <K> the type of keys maintained by this map
+ * @param <V> the type of mapped values
+ *
+ * @author Josh Bloch
+ * @see Object#hashCode()
+ * @see Collection
+ * @see Map
+ * @see HashMap
+ * @see TreeMap
+ * @see Hashtable
+ * @since 1.4
+ */
+public class LinkedHashMap<K,V>
+ extends HashMap<K,V>
+ implements Map<K,V>
+{
+
+ /*
+ * Implementation note. A previous version of this class was
+ * internally structured a little differently. Because superclass
+ * HashMap now uses trees for some of its nodes, class
+ * LinkedHashMap.Entry is now treated as intermediary node class
+ * that can also be converted to tree form. The name of this
+ * class, LinkedHashMap.Entry, is confusing in several ways in its
+ * current context, but cannot be changed. Otherwise, even though
+ * it is not exported outside this package, some existing source
+ * code is known to have relied on a symbol resolution corner case
+ * rule in calls to removeEldestEntry that suppressed compilation
+ * errors due to ambiguous usages. So, we keep the name to
+ * preserve unmodified compilability.
+ *
+ * The changes in node classes also require using two fields
+ * (head, tail) rather than a pointer to a header node to maintain
+ * the doubly-linked before/after list. This class also
+ * previously used a different style of callback methods upon
+ * access, insertion, and removal.
+ */
+
+ /**
+ * HashMap.Node subclass for normal LinkedHashMap entries.
+ */
+ static class Entry<K,V> extends HashMap.Node<K,V> {
+ Entry<K,V> before, after;
+ Entry(int hash, K key, V value, Node<K,V> next) {
+ super(hash, key, value, next);
+ }
+ }
+
+ private static final long serialVersionUID = 3801124242820219131L;
+
+ /**
+ * The head (eldest) of the doubly linked list.
+ */
+ transient LinkedHashMap.Entry<K,V> head;
+
+ /**
+ * The tail (youngest) of the doubly linked list.
+ */
+ transient LinkedHashMap.Entry<K,V> tail;
+
+ /**
+ * The iteration ordering method for this linked hash map: {@code true}
+ * for access-order, {@code false} for insertion-order.
+ *
+ * @serial
+ */
+ final boolean accessOrder;
+
+ // internal utilities
+
+ // link at the end of list
+ private void linkNodeLast(LinkedHashMap.Entry<K,V> p) {
+ LinkedHashMap.Entry<K,V> last = tail;
+ tail = p;
+ if (last == null)
+ head = p;
+ else {
+ p.before = last;
+ last.after = p;
+ }
+ }
+
+ // apply src's links to dst
+ private void transferLinks(LinkedHashMap.Entry<K,V> src,
+ LinkedHashMap.Entry<K,V> dst) {
+ LinkedHashMap.Entry<K,V> b = dst.before = src.before;
+ LinkedHashMap.Entry<K,V> a = dst.after = src.after;
+ if (b == null)
+ head = dst;
+ else
+ b.after = dst;
+ if (a == null)
+ tail = dst;
+ else
+ a.before = dst;
+ }
+
+ // overrides of HashMap hook methods
+
+ void reinitialize() {
+ super.reinitialize();
+ head = tail = null;
+ }
+
+ Node<K,V> newNode(int hash, K key, V value, Node<K,V> e) {
+ LinkedHashMap.Entry<K,V> p =
+ new LinkedHashMap.Entry<>(hash, key, value, e);
+ linkNodeLast(p);
+ return p;
+ }
+
+ Node<K,V> replacementNode(Node<K,V> p, Node<K,V> next) {
+ LinkedHashMap.Entry<K,V> q = (LinkedHashMap.Entry<K,V>)p;
+ LinkedHashMap.Entry<K,V> t =
+ new LinkedHashMap.Entry<>(q.hash, q.key, q.value, next);
+ transferLinks(q, t);
+ return t;
+ }
+
+ TreeNode<K,V> newTreeNode(int hash, K key, V value, Node<K,V> next) {
+ TreeNode<K,V> p = new TreeNode<>(hash, key, value, next);
+ linkNodeLast(p);
+ return p;
+ }
+
+ TreeNode<K,V> replacementTreeNode(Node<K,V> p, Node<K,V> next) {
+ LinkedHashMap.Entry<K,V> q = (LinkedHashMap.Entry<K,V>)p;
+ TreeNode<K,V> t = new TreeNode<>(q.hash, q.key, q.value, next);
+ transferLinks(q, t);
+ return t;
+ }
+
+ void afterNodeRemoval(Node<K,V> e) { // unlink
+ LinkedHashMap.Entry<K,V> p =
+ (LinkedHashMap.Entry<K,V>)e, b = p.before, a = p.after;
+ p.before = p.after = null;
+ if (b == null)
+ head = a;
+ else
+ b.after = a;
+ if (a == null)
+ tail = b;
+ else
+ a.before = b;
+ }
+
+ void afterNodeInsertion(boolean evict) { // possibly remove eldest
+ LinkedHashMap.Entry<K,V> first;
+ if (evict && (first = head) != null && removeEldestEntry(first)) {
+ K key = first.key;
+ removeNode(hash(key), key, null, false, true);
+ }
+ }
+
+ void afterNodeAccess(Node<K,V> e) { // move node to last
+ LinkedHashMap.Entry<K,V> last;
+ if (accessOrder && (last = tail) != e) {
+ LinkedHashMap.Entry<K,V> p =
+ (LinkedHashMap.Entry<K,V>)e, b = p.before, a = p.after;
+ p.after = null;
+ if (b == null)
+ head = a;
+ else
+ b.after = a;
+ if (a != null)
+ a.before = b;
+ else
+ last = b;
+ if (last == null)
+ head = p;
+ else {
+ p.before = last;
+ last.after = p;
+ }
+ tail = p;
+ ++modCount;
+ }
+ }
+
+ void internalWriteEntries(java.io.ObjectOutputStream s) throws IOException {
+ for (LinkedHashMap.Entry<K,V> e = head; e != null; e = e.after) {
+ s.writeObject(e.key);
+ s.writeObject(e.value);
+ }
+ }
+
+ /**
+ * Constructs an empty insertion-ordered {@code LinkedHashMap} instance
+ * with the specified initial capacity and load factor.
+ *
+ * @param initialCapacity the initial capacity
+ * @param loadFactor the load factor
+ * @throws IllegalArgumentException if the initial capacity is negative
+ * or the load factor is nonpositive
+ */
+ public LinkedHashMap(int initialCapacity, float loadFactor) {
+ super(initialCapacity, loadFactor);
+ accessOrder = false;
+ }
+
+ /**
+ * Constructs an empty insertion-ordered {@code LinkedHashMap} instance
+ * with the specified initial capacity and a default load factor (0.75).
+ *
+ * @param initialCapacity the initial capacity
+ * @throws IllegalArgumentException if the initial capacity is negative
+ */
+ public LinkedHashMap(int initialCapacity) {
+ super(initialCapacity);
+ accessOrder = false;
+ }
+
+ /**
+ * Constructs an empty insertion-ordered {@code LinkedHashMap} instance
+ * with the default initial capacity (16) and load factor (0.75).
+ */
+ public LinkedHashMap() {
+ super();
+ accessOrder = false;
+ }
+
+ /**
+ * Constructs an insertion-ordered {@code LinkedHashMap} instance with
+ * the same mappings as the specified map. The {@code LinkedHashMap}
+ * instance is created with a default load factor (0.75) and an initial
+ * capacity sufficient to hold the mappings in the specified map.
+ *
+ * @param m the map whose mappings are to be placed in this map
+ * @throws NullPointerException if the specified map is null
+ */
+ public LinkedHashMap(Map<? extends K, ? extends V> m) {
+ super();
+ accessOrder = false;
+ putMapEntries(m, false);
+ }
+
+ /**
+ * Constructs an empty {@code LinkedHashMap} instance with the
+ * specified initial capacity, load factor and ordering mode.
+ *
+ * @param initialCapacity the initial capacity
+ * @param loadFactor the load factor
+ * @param accessOrder the ordering mode - {@code true} for
+ * access-order, {@code false} for insertion-order
+ * @throws IllegalArgumentException if the initial capacity is negative
+ * or the load factor is nonpositive
+ */
+ public LinkedHashMap(int initialCapacity,
+ float loadFactor,
+ boolean accessOrder) {
+ super(initialCapacity, loadFactor);
+ this.accessOrder = accessOrder;
+ }
+
+
+ /**
+ * Returns {@code true} if this map maps one or more keys to the
+ * specified value.
+ *
+ * @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
+ */
+ public boolean containsValue(Object value) {
+ for (LinkedHashMap.Entry<K,V> e = head; e != null; e = e.after) {
+ V v = e.value;
+ if (v == value || (value != null && value.equals(v)))
+ return true;
+ }
+ return false;
+ }
+
+ /**
+ * 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==null ? k==null :
+ * key.equals(k))}, then this method returns {@code v}; otherwise
+ * it returns {@code null}. (There can be at most one such mapping.)
+ *
+ * <p>A return value of {@code null} does not <i>necessarily</i>
+ * indicate that the map contains no mapping for the key; it's also
+ * possible that the map explicitly maps the key to {@code null}.
+ * The {@link #containsKey containsKey} operation may be used to
+ * distinguish these two cases.
+ */
+ public V get(Object key) {
+ Node<K,V> e;
+ if ((e = getNode(hash(key), key)) == null)
+ return null;
+ if (accessOrder)
+ afterNodeAccess(e);
+ return e.value;
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ public V getOrDefault(Object key, V defaultValue) {
+ Node<K,V> e;
+ if ((e = getNode(hash(key), key)) == null)
+ return defaultValue;
+ if (accessOrder)
+ afterNodeAccess(e);
+ return e.value;
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ public void clear() {
+ super.clear();
+ head = tail = null;
+ }
+
+ /**
+ * Returns {@code true} if this map should remove its eldest entry.
+ * This method is invoked by {@code put} and {@code putAll} after
+ * inserting a new entry into the map. It provides the implementor
+ * with the opportunity to remove the eldest entry each time a new one
+ * is added. This is useful if the map represents a cache: it allows
+ * the map to reduce memory consumption by deleting stale entries.
+ *
+ * <p>Sample use: this override will allow the map to grow up to 100
+ * entries and then delete the eldest entry each time a new entry is
+ * added, maintaining a steady state of 100 entries.
+ * <pre>
+ * private static final int MAX_ENTRIES = 100;
+ *
+ * protected boolean removeEldestEntry(Map.Entry eldest) {
+ * return size() > MAX_ENTRIES;
+ * }
+ * </pre>
+ *
+ * <p>This method typically does not modify the map in any way,
+ * instead allowing the map to modify itself as directed by its
+ * return value. It <i>is</i> permitted for this method to modify
+ * the map directly, but if it does so, it <i>must</i> return
+ * {@code false} (indicating that the map should not attempt any
+ * further modification). The effects of returning {@code true}
+ * after modifying the map from within this method are unspecified.
+ *
+ * <p>This implementation merely returns {@code false} (so that this
+ * map acts like a normal map - the eldest element is never removed).
+ *
+ * @param eldest The least recently inserted entry in the map, or if
+ * this is an access-ordered map, the least recently accessed
+ * entry. This is the entry that will be removed it this
+ * method returns {@code true}. If the map was empty prior
+ * to the {@code put} or {@code putAll} invocation resulting
+ * in this invocation, this will be the entry that was just
+ * inserted; in other words, if the map contains a single
+ * entry, the eldest entry is also the newest.
+ * @return {@code true} if the eldest entry should be removed
+ * from the map; {@code false} if it should be retained.
+ */
+ protected boolean removeEldestEntry(Map.Entry<K,V> eldest) {
+ return false;
+ }
+
+ /**
+ * 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. If the map is modified
+ * while an iteration over the set is in progress (except through
+ * the iterator's own {@code remove} operation), the results of
+ * the iteration are undefined. 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. It does not support the {@code add} or {@code addAll}
+ * operations.
+ * Its {@link Spliterator} typically provides faster sequential
+ * performance but much poorer parallel performance than that of
+ * {@code HashMap}.
+ *
+ * @return a set view of the keys contained in this map
+ */
+ public Set<K> keySet() {
+ Set<K> ks = keySet;
+ if (ks == null) {
+ ks = new LinkedKeySet();
+ keySet = ks;
+ }
+ return ks;
+ }
+
+ final class LinkedKeySet extends AbstractSet<K> {
+ public final int size() { return size; }
+ public final void clear() { LinkedHashMap.this.clear(); }
+ public final Iterator<K> iterator() {
+ return new LinkedKeyIterator();
+ }
+ public final boolean contains(Object o) { return containsKey(o); }
+ public final boolean remove(Object key) {
+ return removeNode(hash(key), key, null, false, true) != null;
+ }
+ public final Spliterator<K> spliterator() {
+ return Spliterators.spliterator(this, Spliterator.SIZED |
+ Spliterator.ORDERED |
+ Spliterator.DISTINCT);
+ }
+ public final void forEach(Consumer<? super K> action) {
+ if (action == null)
+ throw new NullPointerException();
+ int mc = modCount;
+ for (LinkedHashMap.Entry<K,V> e = head; e != null; e = e.after)
+ action.accept(e.key);
+ if (modCount != mc)
+ throw new ConcurrentModificationException();
+ }
+ }
+
+ /**
+ * 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. If the map is
+ * modified while an iteration over the collection is in progress
+ * (except through the iterator's own {@code remove} operation),
+ * the results of the iteration are undefined. The collection
+ * supports element removal, which removes the corresponding
+ * mapping from the 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.
+ * Its {@link Spliterator} typically provides faster sequential
+ * performance but much poorer parallel performance than that of
+ * {@code HashMap}.
+ *
+ * @return a view of the values contained in this map
+ */
+ public Collection<V> values() {
+ Collection<V> vs = values;
+ if (vs == null) {
+ vs = new LinkedValues();
+ values = vs;
+ }
+ return vs;
+ }
+
+ final class LinkedValues extends AbstractCollection<V> {
+ public final int size() { return size; }
+ public final void clear() { LinkedHashMap.this.clear(); }
+ public final Iterator<V> iterator() {
+ return new LinkedValueIterator();
+ }
+ public final boolean contains(Object o) { return containsValue(o); }
+ public final Spliterator<V> spliterator() {
+ return Spliterators.spliterator(this, Spliterator.SIZED |
+ Spliterator.ORDERED);
+ }
+ public final void forEach(Consumer<? super V> action) {
+ if (action == null)
+ throw new NullPointerException();
+ int mc = modCount;
+ for (LinkedHashMap.Entry<K,V> e = head; e != null; e = e.after)
+ action.accept(e.value);
+ if (modCount != mc)
+ throw new ConcurrentModificationException();
+ }
+ }
+
+ /**
+ * 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. If the map is modified
+ * while an iteration over the set is in progress (except through
+ * the iterator's own {@code remove} operation, or through the
+ * {@code setValue} operation on a map entry returned by the
+ * iterator) the results of the iteration are undefined. 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. It does not support the
+ * {@code add} or {@code addAll} operations.
+ * Its {@link Spliterator} typically provides faster sequential
+ * performance but much poorer parallel performance than that of
+ * {@code HashMap}.
+ *
+ * @return a set view of the mappings contained in this map
+ */
+ public Set<Map.Entry<K,V>> entrySet() {
+ Set<Map.Entry<K,V>> es;
+ return (es = entrySet) == null ? (entrySet = new LinkedEntrySet()) : es;
+ }
+
+ final class LinkedEntrySet extends AbstractSet<Map.Entry<K,V>> {
+ public final int size() { return size; }
+ public final void clear() { LinkedHashMap.this.clear(); }
+ public final Iterator<Map.Entry<K,V>> iterator() {
+ return new LinkedEntryIterator();
+ }
+ public final boolean contains(Object o) {
+ if (!(o instanceof Map.Entry))
+ return false;
+ Map.Entry<?,?> e = (Map.Entry<?,?>) o;
+ Object key = e.getKey();
+ Node<K,V> candidate = getNode(hash(key), key);
+ return candidate != null && candidate.equals(e);
+ }
+ public final boolean remove(Object o) {
+ if (o instanceof Map.Entry) {
+ Map.Entry<?,?> e = (Map.Entry<?,?>) o;
+ Object key = e.getKey();
+ Object value = e.getValue();
+ return removeNode(hash(key), key, value, true, true) != null;
+ }
+ return false;
+ }
+ public final Spliterator<Map.Entry<K,V>> spliterator() {
+ return Spliterators.spliterator(this, Spliterator.SIZED |
+ Spliterator.ORDERED |
+ Spliterator.DISTINCT);
+ }
+ public final void forEach(Consumer<? super Map.Entry<K,V>> action) {
+ if (action == null)
+ throw new NullPointerException();
+ int mc = modCount;
+ for (LinkedHashMap.Entry<K,V> e = head; e != null; e = e.after)
+ action.accept(e);
+ if (modCount != mc)
+ throw new ConcurrentModificationException();
+ }
+ }
+
+ // Map overrides
+
+ public void forEach(BiConsumer<? super K, ? super V> action) {
+ if (action == null)
+ throw new NullPointerException();
+ int mc = modCount;
+ for (LinkedHashMap.Entry<K,V> e = head; e != null; e = e.after)
+ action.accept(e.key, e.value);
+ if (modCount != mc)
+ throw new ConcurrentModificationException();
+ }
+
+ public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function) {
+ if (function == null)
+ throw new NullPointerException();
+ int mc = modCount;
+ for (LinkedHashMap.Entry<K,V> e = head; e != null; e = e.after)
+ e.value = function.apply(e.key, e.value);
+ if (modCount != mc)
+ throw new ConcurrentModificationException();
+ }
+
+ // Iterators
+
+ abstract class LinkedHashIterator {
+ LinkedHashMap.Entry<K,V> next;
+ LinkedHashMap.Entry<K,V> current;
+ int expectedModCount;
+
+ LinkedHashIterator() {
+ next = head;
+ expectedModCount = modCount;
+ current = null;
+ }
+
+ public final boolean hasNext() {
+ return next != null;
+ }
+
+ final LinkedHashMap.Entry<K,V> nextNode() {
+ LinkedHashMap.Entry<K,V> e = next;
+ if (modCount != expectedModCount)
+ throw new ConcurrentModificationException();
+ if (e == null)
+ throw new NoSuchElementException();
+ current = e;
+ next = e.after;
+ return e;
+ }
+
+ public final void remove() {
+ Node<K,V> p = current;
+ if (p == null)
+ throw new IllegalStateException();
+ if (modCount != expectedModCount)
+ throw new ConcurrentModificationException();
+ current = null;
+ removeNode(p.hash, p.key, null, false, false);
+ expectedModCount = modCount;
+ }
+ }
+
+ final class LinkedKeyIterator extends LinkedHashIterator
+ implements Iterator<K> {
+ public final K next() { return nextNode().getKey(); }
+ }
+
+ final class LinkedValueIterator extends LinkedHashIterator
+ implements Iterator<V> {
+ public final V next() { return nextNode().value; }
+ }
+
+ final class LinkedEntryIterator extends LinkedHashIterator
+ implements Iterator<Map.Entry<K,V>> {
+ public final Map.Entry<K,V> next() { return nextNode(); }
+ }
+
+
+}