--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.jfr/share/classes/jdk/jfr/internal/LongMap.java Wed Oct 30 19:43:52 2019 +0100
@@ -0,0 +1,257 @@
+/*
+ * Copyright (c) 2019, 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 jdk.jfr.internal;
+
+import java.util.BitSet;
+import java.util.function.Consumer;
+import java.util.function.LongConsumer;
+
+@SuppressWarnings("unchecked")
+public final class LongMap<T> {
+ private static final int MAXIMUM_CAPACITY = 1 << 30;
+ private static final long[] EMPTY_KEYS = new long[0];
+ private static final Object[] EMPTY_OBJECTS = new Object[0];
+ private static final int DEFAULT_SIZE = 32;
+ private static final Object NULL_OBJECT = new Object();
+
+ private final int bitCount;
+ private BitSet bitSet;
+ private long[] keys = EMPTY_KEYS;
+ private T[] objects = (T[]) EMPTY_OBJECTS;
+ private int count;
+ private int shift;
+
+ public LongMap() {
+ this.bitCount = 0;
+ }
+
+ public LongMap(int markBits) {
+ this.bitCount = markBits;
+ this.bitSet = new BitSet();
+ }
+
+ // Should be 2^n
+ private void initialize(int capacity) {
+ keys = new long[capacity];
+ objects = (T[]) new Object[capacity];
+ shift = 64 - (31 - Integer.numberOfLeadingZeros(capacity));
+ }
+
+ public void claimBits() {
+ // flip last bit back and forth to make bitset expand to max size
+ int lastBit = bitSetIndex(objects.length - 1, bitCount -1);
+ bitSet.flip(lastBit);
+ bitSet.flip(lastBit);
+ }
+
+ public void setId(long id, int bitIndex) {
+ int bitSetIndex = bitSetIndex(tableIndexOf(id), bitIndex);
+ bitSet.set(bitSetIndex, true);
+ }
+
+ public void clearId(long id, int bitIndex) {
+ int bitSetIndex = bitSetIndex(tableIndexOf(id), bitIndex);
+ bitSet.set(bitSetIndex, false);
+ }
+
+ public boolean isSetId(long id, int bitIndex) {
+ int bitSetIndex = bitSetIndex(tableIndexOf(id), bitIndex);
+ return bitSet.get(bitSetIndex);
+ }
+
+ private int bitSetIndex(int tableIndex, int bitIndex) {
+ return bitCount * tableIndex + bitIndex;
+ }
+
+ private int tableIndexOf(long id) {
+ int index = index(id);
+ while (true) {
+ if (objects[index] == null) {
+ throw new InternalError("Unknown id");
+ }
+ if (keys[index] == id) {
+ return index;
+ }
+ index++;
+ if (index == keys.length) {
+ index = 0;
+ }
+ }
+ }
+
+ public boolean hasKey(long id) {
+ int index = index(id);
+ while (true) {
+ if (objects[index] == null) {
+ return false;
+ }
+ if (keys[index] == id) {
+ return true;
+ }
+ index++;
+ if (index == keys.length) {
+ index = 0;
+ }
+ }
+ }
+
+ public void expand(int size) {
+ int l = 4 * size / 3;
+ if (l <= keys.length) {
+ return;
+ }
+ int n = tableSizeFor(l);
+ LongMap<T> temp = new LongMap<>(bitCount);
+ temp.initialize(n);
+ // Optimization, avoid growing while copying bits
+ if (bitCount > 0 && !bitSet.isEmpty()) {
+ temp.claimBits();
+ claimBits();
+ }
+ for (int tIndex = 0; tIndex < keys.length; tIndex++) {
+ T o = objects[tIndex];
+ if (o != null) {
+ long key = keys[tIndex];
+ temp.put(key, o);
+ if (bitCount != 0) {
+ for (int bIndex = 0; bIndex < bitCount; bIndex++) {
+ boolean bitValue = isSetId(key, bIndex);
+ if (bitValue) {
+ temp.setId(key, bIndex);
+ }
+ }
+ }
+ }
+ }
+ keys = temp.keys;
+ objects = temp.objects;
+ shift = temp.shift;
+ bitSet = temp.bitSet;
+ }
+
+ public void put(long id, T object) {
+ if (keys == EMPTY_KEYS) {
+ // Lazy initialization
+ initialize(DEFAULT_SIZE);
+ }
+ if (object == null) {
+ object = (T) NULL_OBJECT;
+ }
+
+ int index = index(id);
+ // probe for empty slot
+ while (true) {
+ if (objects[index] == null) {
+ keys[index] = id;
+ objects[index] = object;
+ count++;
+ // Don't expand lazy since it
+ // can cause resize when replacing
+ // an object.
+ if (count > 3 * keys.length / 4) {
+ expand(2 * keys.length);
+ }
+ return;
+ }
+ // if it already exists, replace
+ if (keys[index] == id) {
+ objects[index] = object;
+ return;
+ }
+ index++;
+ if (index == keys.length) {
+ index = 0;
+ }
+ }
+ }
+ public T getAt(int tableIndex) {
+ T o = objects[tableIndex];
+ return o == NULL_OBJECT ? null : o;
+ }
+
+ public T get(long id) {
+ if (keys == EMPTY_KEYS) {
+ return null;
+ }
+ int index = index(id);
+ while (true) {
+ if (objects[index] == null) {
+ return null;
+ }
+ if (keys[index] == id) {
+ return getAt(index);
+ }
+ index++;
+ if (index == keys.length) {
+ index = 0;
+ }
+ }
+ }
+
+ private int index(long id) {
+ return (int) ((id * -7046029254386353131L) >>> shift);
+ }
+
+ // Copied from HashMap::tableSizeFor
+ private static final int tableSizeFor(int cap) {
+ int n = -1 >>> Integer.numberOfLeadingZeros(cap - 1);
+ return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
+ }
+
+ public void forEachKey(LongConsumer keyTraverser) {
+ for (int i = 0; i < keys.length; i++) {
+ if (objects[i] != null) {
+ keyTraverser.accept(keys[i]);
+ }
+ }
+ }
+
+ public void forEach(Consumer<T> consumer) {
+ for (int i = 0; i < keys.length; i++) {
+ T o = objects[i];
+ if (o != null) {
+ consumer.accept(o);
+ }
+ }
+ }
+
+ public int size() {
+ return count;
+ }
+
+ public String toString() {
+ StringBuilder sb = new StringBuilder();
+ for (int i = 0; i < objects.length; i++) {
+ sb.append(i);
+ sb.append(": id=");
+ sb.append(keys[i]);
+ sb.append(" ");
+ sb.append(objects[i]);
+ sb.append("\n");
+ }
+ return sb.toString();
+ }
+}