5047N/A/*
5047N/A * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
5047N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5047N/A *
5047N/A * This code is free software; you can redistribute it and/or modify it
5047N/A * under the terms of the GNU General Public License version 2 only, as
5047N/A * published by the Free Software Foundation.
5047N/A *
5047N/A * This code is distributed in the hope that it will be useful, but WITHOUT
5047N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
5047N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
5047N/A * version 2 for more details (a copy is included in the LICENSE file that
5047N/A * accompanied this code).
5047N/A *
5047N/A * You should have received a copy of the GNU General Public License version
5047N/A * 2 along with this work; if not, write to the Free Software Foundation,
5047N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
5047N/A *
5047N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
5047N/A * or visit www.oracle.com if you need additional information or have any
5047N/A * questions.
5047N/A */
5047N/A
5047N/A/*
5047N/A * @test
5047N/A * @bug 7126277
5383N/A * @run main Collisions -shortrun
5385N/A * @run main/othervm -Djdk.map.althashing.threshold=0 Collisions -shortrun
5047N/A * @summary Ensure Maps behave well with lots of hashCode() collisions.
5047N/A * @author Mike Duigou
5047N/A */
5047N/Aimport java.util.*;
5047N/Aimport java.util.concurrent.ConcurrentHashMap;
5047N/Aimport java.util.concurrent.ConcurrentSkipListMap;
5047N/A
5047N/Apublic class Collisions {
5047N/A
5383N/A /**
5383N/A * Number of elements per map.
5383N/A */
5383N/A private static final int TEST_SIZE = 5000;
5383N/A
5047N/A final static class HashableInteger implements Comparable<HashableInteger> {
5047N/A
5047N/A final int value;
5047N/A final int hashmask; //yes duplication
5047N/A
5047N/A HashableInteger(int value, int hashmask) {
5047N/A this.value = value;
5047N/A this.hashmask = hashmask;
5047N/A }
5047N/A
5047N/A @Override
5047N/A public boolean equals(Object obj) {
5047N/A if (obj instanceof HashableInteger) {
5047N/A HashableInteger other = (HashableInteger) obj;
5047N/A
5047N/A return other.value == value;
5047N/A }
5047N/A
5047N/A return false;
5047N/A }
5047N/A
5047N/A @Override
5047N/A public int hashCode() {
5047N/A return value % hashmask;
5047N/A }
5047N/A
5047N/A @Override
5047N/A public int compareTo(HashableInteger o) {
5047N/A return value - o.value;
5047N/A }
5047N/A
5383N/A @Override
5047N/A public String toString() {
5047N/A return Integer.toString(value);
5047N/A }
5047N/A }
5047N/A
5383N/A private static Object[][] makeTestData(int size) {
5383N/A HashableInteger UNIQUE_OBJECTS[] = new HashableInteger[size];
5383N/A HashableInteger COLLIDING_OBJECTS[] = new HashableInteger[size];
5383N/A String UNIQUE_STRINGS[] = new String[size];
5383N/A String COLLIDING_STRINGS[] = new String[size];
5047N/A
5383N/A for (int i = 0; i < size; i++) {
5047N/A UNIQUE_OBJECTS[i] = new HashableInteger(i, Integer.MAX_VALUE);
5047N/A COLLIDING_OBJECTS[i] = new HashableInteger(i, 10);
5047N/A UNIQUE_STRINGS[i] = unhash(i);
5047N/A COLLIDING_STRINGS[i] = (0 == i % 2)
5047N/A ? UNIQUE_STRINGS[i / 2]
5047N/A : "\u0000\u0000\u0000\u0000\u0000" + COLLIDING_STRINGS[i - 1];
5047N/A }
5047N/A
5383N/A return new Object[][] {
5047N/A new Object[]{"Unique Objects", UNIQUE_OBJECTS},
5047N/A new Object[]{"Colliding Objects", COLLIDING_OBJECTS},
5047N/A new Object[]{"Unique Strings", UNIQUE_STRINGS},
5047N/A new Object[]{"Colliding Strings", COLLIDING_STRINGS}
5047N/A };
5047N/A }
5047N/A
5047N/A /**
5047N/A * Returns a string with a hash equal to the argument.
5047N/A *
5047N/A * @return string with a hash equal to the argument.
5047N/A */
5047N/A public static String unhash(int target) {
5047N/A StringBuilder answer = new StringBuilder();
5047N/A if (target < 0) {
5047N/A // String with hash of Integer.MIN_VALUE, 0x80000000
5047N/A answer.append("\\u0915\\u0009\\u001e\\u000c\\u0002");
5047N/A
5047N/A if (target == Integer.MIN_VALUE) {
5047N/A return answer.toString();
5047N/A }
5047N/A // Find target without sign bit set
5047N/A target = target & Integer.MAX_VALUE;
5047N/A }
5047N/A
5047N/A unhash0(answer, target);
5047N/A return answer.toString();
5047N/A }
5047N/A
5047N/A private static void unhash0(StringBuilder partial, int target) {
5047N/A int div = target / 31;
5047N/A int rem = target % 31;
5047N/A
5047N/A if (div <= Character.MAX_VALUE) {
5047N/A if (div != 0) {
5047N/A partial.append((char) div);
5047N/A }
5047N/A partial.append((char) rem);
5047N/A } else {
5047N/A unhash0(partial, div);
5047N/A partial.append((char) rem);
5047N/A }
5047N/A }
5047N/A
5047N/A private static void realMain(String[] args) throws Throwable {
5383N/A boolean shortRun = args.length > 0 && args[0].equals("-shortrun");
5383N/A
5383N/A Object[][] mapKeys = makeTestData(shortRun ? (TEST_SIZE / 2) : TEST_SIZE);
5383N/A
5383N/A // loop through data sets
5383N/A for (Object[] keys_desc : mapKeys) {
5383N/A Map<Object, Object>[] maps = (Map<Object, Object>[]) new Map[]{
5383N/A new HashMap<>(),
5047N/A new Hashtable<>(),
5047N/A new IdentityHashMap<>(),
5047N/A new LinkedHashMap<>(),
5383N/A new TreeMap<>(),
5047N/A new WeakHashMap<>(),
5383N/A new ConcurrentHashMap<>(),
5047N/A new ConcurrentSkipListMap<>()
5047N/A };
5047N/A
5383N/A // for each map type.
5383N/A for (Map<Object, Object> map : maps) {
5047N/A String desc = (String) keys_desc[0];
5047N/A Object[] keys = (Object[]) keys_desc[1];
5129N/A try {
5383N/A testMap(map, desc, keys);
5129N/A } catch(Exception all) {
5129N/A unexpected("Failed for " + map.getClass().getName() + " with " + desc, all);
5129N/A }
5047N/A }
5047N/A }
5047N/A }
5047N/A
5129N/A private static <T> void testMap(Map<T, T> map, String keys_desc, T[] keys) {
5129N/A System.out.println(map.getClass() + " : " + keys_desc);
5129N/A System.out.flush();
5047N/A testInsertion(map, keys_desc, keys);
5047N/A
5047N/A if (keys[0] instanceof HashableInteger) {
5129N/A testIntegerIteration((Map<HashableInteger, HashableInteger>) map, (HashableInteger[]) keys);
5047N/A } else {
5129N/A testStringIteration((Map<String, String>) map, (String[]) keys);
5047N/A }
5047N/A
5047N/A testContainsKey(map, keys_desc, keys);
5047N/A
5047N/A testRemove(map, keys_desc, keys);
5047N/A
5129N/A map.clear();
5129N/A testInsertion(map, keys_desc, keys);
5129N/A testKeysIteratorRemove(map, keys_desc, keys);
5129N/A
5129N/A map.clear();
5129N/A testInsertion(map, keys_desc, keys);
5129N/A testValuesIteratorRemove(map, keys_desc, keys);
5129N/A
5129N/A map.clear();
5129N/A testInsertion(map, keys_desc, keys);
5129N/A testEntriesIteratorRemove(map, keys_desc, keys);
5129N/A
5047N/A check(map.isEmpty());
5047N/A }
5047N/A
5129N/A private static <T> void testInsertion(Map<T, T> map, String keys_desc, T[] keys) {
5047N/A check("map empty", (map.size() == 0) && map.isEmpty());
5047N/A
5047N/A for (int i = 0; i < keys.length; i++) {
5047N/A check(String.format("insertion: map expected size m%d != i%d", map.size(), i),
5047N/A map.size() == i);
5129N/A check(String.format("insertion: put(%s[%d])", keys_desc, i), null == map.put(keys[i], keys[i]));
5047N/A check(String.format("insertion: containsKey(%s[%d])", keys_desc, i), map.containsKey(keys[i]));
5129N/A check(String.format("insertion: containsValue(%s[%d])", keys_desc, i), map.containsValue(keys[i]));
5047N/A }
5047N/A
5047N/A check(String.format("map expected size m%d != k%d", map.size(), keys.length),
5047N/A map.size() == keys.length);
5047N/A }
5047N/A
5129N/A private static void testIntegerIteration(Map<HashableInteger, HashableInteger> map, HashableInteger[] keys) {
5047N/A check(String.format("map expected size m%d != k%d", map.size(), keys.length),
5047N/A map.size() == keys.length);
5047N/A
5047N/A BitSet all = new BitSet(keys.length);
5129N/A for (Map.Entry<HashableInteger, HashableInteger> each : map.entrySet()) {
5047N/A check("Iteration: key already seen", !all.get(each.getKey().value));
5047N/A all.set(each.getKey().value);
5047N/A }
5047N/A
5047N/A all.flip(0, keys.length);
5047N/A check("Iteration: some keys not visited", all.isEmpty());
5047N/A
5047N/A for (HashableInteger each : map.keySet()) {
5047N/A check("Iteration: key already seen", !all.get(each.value));
5047N/A all.set(each.value);
5047N/A }
5047N/A
5047N/A all.flip(0, keys.length);
5047N/A check("Iteration: some keys not visited", all.isEmpty());
5047N/A
5047N/A int count = 0;
5129N/A for (HashableInteger each : map.values()) {
5047N/A count++;
5047N/A }
5047N/A
5047N/A check(String.format("Iteration: value count matches size m%d != c%d", map.size(), count),
5047N/A map.size() == count);
5047N/A }
5047N/A
5129N/A private static void testStringIteration(Map<String, String> map, String[] keys) {
5047N/A check(String.format("map expected size m%d != k%d", map.size(), keys.length),
5047N/A map.size() == keys.length);
5047N/A
5047N/A BitSet all = new BitSet(keys.length);
5129N/A for (Map.Entry<String, String> each : map.entrySet()) {
5047N/A String key = each.getKey();
5047N/A boolean longKey = key.length() > 5;
5047N/A int index = key.hashCode() + (longKey ? keys.length / 2 : 0);
5047N/A check("key already seen", !all.get(index));
5047N/A all.set(index);
5047N/A }
5047N/A
5047N/A all.flip(0, keys.length);
5047N/A check("some keys not visited", all.isEmpty());
5047N/A
5047N/A for (String each : map.keySet()) {
5047N/A boolean longKey = each.length() > 5;
5047N/A int index = each.hashCode() + (longKey ? keys.length / 2 : 0);
5047N/A check("key already seen", !all.get(index));
5047N/A all.set(index);
5047N/A }
5047N/A
5047N/A all.flip(0, keys.length);
5047N/A check("some keys not visited", all.isEmpty());
5047N/A
5047N/A int count = 0;
5129N/A for (String each : map.values()) {
5047N/A count++;
5047N/A }
5047N/A
5047N/A check(String.format("value count matches size m%d != k%d", map.size(), keys.length),
5047N/A map.size() == keys.length);
5047N/A }
5047N/A
5129N/A private static <T> void testContainsKey(Map<T, T> map, String keys_desc, T[] keys) {
5047N/A for (int i = 0; i < keys.length; i++) {
5047N/A T each = keys[i];
5047N/A check("containsKey: " + keys_desc + "[" + i + "]" + each, map.containsKey(each));
5047N/A }
5047N/A }
5047N/A
5129N/A private static <T> void testRemove(Map<T, T> map, String keys_desc, T[] keys) {
5047N/A check(String.format("remove: map expected size m%d != k%d", map.size(), keys.length),
5047N/A map.size() == keys.length);
5047N/A
5047N/A for (int i = 0; i < keys.length; i++) {
5047N/A T each = keys[i];
5047N/A check("remove: " + keys_desc + "[" + i + "]" + each, null != map.remove(each));
5047N/A }
5047N/A
5047N/A check(String.format("remove: map empty. size=%d", map.size()),
5047N/A (map.size() == 0) && map.isEmpty());
5047N/A }
5129N/A
5129N/A private static <T> void testKeysIteratorRemove(Map<T, T> map, String keys_desc, T[] keys) {
5129N/A check(String.format("remove: map expected size m%d != k%d", map.size(), keys.length),
5129N/A map.size() == keys.length);
5129N/A
5129N/A Iterator<T> each = map.keySet().iterator();
5129N/A while (each.hasNext()) {
5129N/A T t = each.next();
5129N/A each.remove();
5129N/A check("not removed: " + each, !map.containsKey(t) );
5129N/A }
5129N/A
5129N/A check(String.format("remove: map empty. size=%d", map.size()),
5129N/A (map.size() == 0) && map.isEmpty());
5129N/A }
5129N/A
5129N/A private static <T> void testValuesIteratorRemove(Map<T, T> map, String keys_desc, T[] keys) {
5129N/A check(String.format("remove: map expected size m%d != k%d", map.size(), keys.length),
5129N/A map.size() == keys.length);
5129N/A
5129N/A Iterator<T> each = map.values().iterator();
5129N/A while (each.hasNext()) {
5129N/A T t = each.next();
5129N/A each.remove();
5129N/A check("not removed: " + each, !map.containsValue(t) );
5129N/A }
5129N/A
5129N/A check(String.format("remove: map empty. size=%d", map.size()),
5129N/A (map.size() == 0) && map.isEmpty());
5129N/A }
5129N/A
5129N/A private static <T> void testEntriesIteratorRemove(Map<T, T> map, String keys_desc, T[] keys) {
5129N/A check(String.format("remove: map expected size m%d != k%d", map.size(), keys.length),
5129N/A map.size() == keys.length);
5129N/A
5129N/A Iterator<Map.Entry<T,T>> each = map.entrySet().iterator();
5129N/A while (each.hasNext()) {
5129N/A Map.Entry<T,T> t = each.next();
5129N/A T key = t.getKey();
5129N/A T value = t.getValue();
5129N/A each.remove();
5129N/A check("not removed: " + each, (map instanceof IdentityHashMap) || !map.entrySet().contains(t) );
5129N/A check("not removed: " + each, !map.containsKey(key) );
5129N/A check("not removed: " + each, !map.containsValue(value));
5129N/A }
5129N/A
5129N/A check(String.format("remove: map empty. size=%d", map.size()),
5129N/A (map.size() == 0) && map.isEmpty());
5129N/A }
5129N/A
5047N/A //--------------------- Infrastructure ---------------------------
5047N/A static volatile int passed = 0, failed = 0;
5047N/A
5047N/A static void pass() {
5047N/A passed++;
5047N/A }
5047N/A
5047N/A static void fail() {
5047N/A failed++;
5047N/A (new Error("Failure")).printStackTrace(System.err);
5047N/A }
5047N/A
5047N/A static void fail(String msg) {
5047N/A failed++;
5047N/A (new Error("Failure: " + msg)).printStackTrace(System.err);
5047N/A }
5047N/A
5047N/A static void abort() {
5047N/A fail();
5047N/A System.exit(1);
5047N/A }
5047N/A
5047N/A static void abort(String msg) {
5047N/A fail(msg);
5047N/A System.exit(1);
5047N/A }
5047N/A
5047N/A static void unexpected(String msg, Throwable t) {
5047N/A System.err.println("Unexpected: " + msg);
5047N/A unexpected(t);
5047N/A }
5047N/A
5047N/A static void unexpected(Throwable t) {
5047N/A failed++;
5047N/A t.printStackTrace(System.err);
5047N/A }
5047N/A
5047N/A static void check(boolean cond) {
5047N/A if (cond) {
5047N/A pass();
5047N/A } else {
5047N/A fail();
5047N/A }
5047N/A }
5047N/A
5047N/A static void check(String desc, boolean cond) {
5047N/A if (cond) {
5047N/A pass();
5047N/A } else {
5047N/A fail(desc);
5047N/A }
5047N/A }
5047N/A
5047N/A static void equal(Object x, Object y) {
5047N/A if (Objects.equals(x, y)) {
5047N/A pass();
5047N/A } else {
5047N/A fail(x + " not equal to " + y);
5047N/A }
5047N/A }
5047N/A
5047N/A public static void main(String[] args) throws Throwable {
5383N/A Thread.currentThread().setName(Collisions.class.getName());
5047N/A// Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
5047N/A try {
5047N/A realMain(args);
5047N/A } catch (Throwable t) {
5047N/A unexpected(t);
5047N/A }
5047N/A
5047N/A System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
5047N/A if (failed > 0) {
5047N/A throw new Error("Some tests failed");
5047N/A }
5047N/A }
5047N/A}