jdk-24/jdk/test/java/util/Collection/BiggernYours.java
Mike Duigou 705c53b045 7126277: Alternative String hashing implementation
All of the hashing based Map implementations: HashMap, Hashtable, LinkedHashMap, WeakHashMap and ConcurrentHashMap are modified to use an enhanced hashing algorithm for string keys when the capacity of the hash table has ever grown beyond 512 entries. The enhanced hashing implementation uses the murmur3 hashing algorithm along with random hash seeds and index masks. These enhancements mitigate cases where colliding String hash values could result in a performance bottleneck.

Reviewed-by: alanb, forax, dl
2012-05-30 22:18:37 -07:00

251 lines
9.1 KiB
Java

/*
* Copyright (c) 2006, 2010, 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.
*
* 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.
*/
/*
* @test
* @bug 6415641 6377302
* @summary Concurrent collections are permitted to lie about their size
* @author Martin Buchholz
*/
import java.io.*;
import java.util.*;
import java.util.concurrent.*;
@SuppressWarnings("unchecked")
public class BiggernYours {
static final Random rnd = new Random(18675309);
static void compareCollections(Collection c1, Collection c2) {
Object[] c1Array = c1.toArray();
Object[] c2Array = c2.toArray();
check(c1Array.length == c2Array.length);
for(Object aC1 : c1Array) {
boolean found = false;
for(Object aC2 : c2Array) {
if(Objects.equals(aC1, aC2)) {
found = true;
break;
}
}
if(!found)
fail(aC1 + " not found in " + Arrays.toString(c2Array));
}
}
static void compareMaps(Map m1, Map m2) {
compareCollections(m1.keySet(),
m2.keySet());
compareCollections(m1.values(),
m2.values());
compareCollections(m1.entrySet(),
m2.entrySet());
}
static void compareNavigableMaps(NavigableMap m1, NavigableMap m2) {
compareMaps(m1, m2);
compareMaps(m1.descendingMap(),
m2.descendingMap());
compareMaps(m1.tailMap(Integer.MIN_VALUE),
m2.tailMap(Integer.MIN_VALUE));
compareMaps(m1.headMap(Integer.MAX_VALUE),
m2.headMap(Integer.MAX_VALUE));
}
static void compareNavigableSets(NavigableSet s1, NavigableSet s2) {
compareCollections(s1, s2);
compareCollections(s1.descendingSet(),
s2.descendingSet());
compareCollections(s1.tailSet(Integer.MIN_VALUE),
s2.tailSet(Integer.MIN_VALUE));
}
static abstract class MapFrobber { abstract void frob(Map m); }
static abstract class SetFrobber { abstract void frob(Set s); }
static abstract class ColFrobber { abstract void frob(Collection c); }
static ColFrobber adder(final int i) {
return new ColFrobber() {void frob(Collection c) { c.add(i); }};
}
static final ColFrobber[] adders =
{ adder(1), adder(3), adder(2) };
static MapFrobber putter(final int k, final int v) {
return new MapFrobber() {void frob(Map m) { m.put(k,v); }};
}
static final MapFrobber[] putters =
{ putter(1, -2), putter(3, -6), putter(2, -4) };
static void unexpected(Throwable t, Object suspect) {
System.out.println(suspect.getClass());
unexpected(t);
}
static void testCollections(Collection c1, Collection c2) {
try {
compareCollections(c1, c2);
for (ColFrobber adder : adders) {
for (Collection c : new Collection[]{c1, c2})
adder.frob(c);
compareCollections(c1, c2);
}
} catch (Throwable t) { unexpected(t, c1); }
}
static void testNavigableSets(NavigableSet s1, NavigableSet s2) {
try {
compareNavigableSets(s1, s2);
for (ColFrobber adder : adders) {
for (Set s : new Set[]{s1, s2})
adder.frob(s);
compareNavigableSets(s1, s2);
}
} catch (Throwable t) { unexpected(t, s1); }
}
static void testMaps(Map m1, Map m2) {
try {
compareMaps(m1, m2);
for (MapFrobber putter : putters) {
for (Map m : new Map[]{m1, m2})
putter.frob(m);
compareMaps(m1, m2);
}
} catch (Throwable t) { unexpected(t, m1); }
}
static void testNavigableMaps(NavigableMap m1, NavigableMap m2) {
try {
compareNavigableMaps(m1, m2);
for (MapFrobber putter : putters) {
for (Map m : new Map[]{m1, m2})
putter.frob(m);
compareNavigableMaps(m1, m2);
}
} catch (Throwable t) { unexpected(t, m1); }
}
static int randomize(int size) { return rnd.nextInt(size + 2); }
@SuppressWarnings("serial")
private static void realMain(String[] args) throws Throwable {
testNavigableMaps(
new ConcurrentSkipListMap(),
new ConcurrentSkipListMap() {
public int size() {return randomize(super.size());}});
testNavigableSets(
new ConcurrentSkipListSet(),
new ConcurrentSkipListSet() {
public int size() {return randomize(super.size());}});
testCollections(
new CopyOnWriteArraySet(),
new CopyOnWriteArraySet() {
public int size() {return randomize(super.size());}});
testCollections(
new CopyOnWriteArrayList(),
new CopyOnWriteArrayList() {
public int size() {return randomize(super.size());}});
testCollections(
new TreeSet(),
new TreeSet() {
public int size() {return randomize(super.size());}});
testMaps(
new ConcurrentHashMap(),
new ConcurrentHashMap() {
public int size() {return randomize(super.size());}});
testCollections(
new ConcurrentLinkedDeque(),
new ConcurrentLinkedDeque() {
public int size() {return randomize(super.size());}});
testCollections(
new ConcurrentLinkedQueue(),
new ConcurrentLinkedQueue() {
public int size() {return randomize(super.size());}});
testCollections(
new LinkedTransferQueue(),
new LinkedTransferQueue() {
public int size() {return randomize(super.size());}});
testCollections(
new LinkedBlockingQueue(),
new LinkedBlockingQueue() {
public int size() {return randomize(super.size());}});
testCollections(
new LinkedBlockingDeque(),
new LinkedBlockingDeque() {
public int size() {return randomize(super.size());}});
testCollections(
new ArrayBlockingQueue(5),
new ArrayBlockingQueue(5) {
public int size() {return randomize(super.size());}});
testCollections(
new PriorityBlockingQueue(5),
new PriorityBlockingQueue(5) {
public int size() {return randomize(super.size());}});
}
//--------------------- Infrastructure ---------------------------
static volatile int passed = 0, failed = 0;
static void pass() {passed++;}
static void fail() {failed++; Thread.dumpStack();}
static void fail(String msg) {System.out.println(msg); fail();}
static void unexpected(Throwable t) {failed++; t.printStackTrace();}
static void check(boolean cond) {if (cond) pass(); else fail();}
static void equal(Object x, Object y) {
if (x == null ? y == null : x.equals(y)) pass();
else fail(x + " not equal to " + y);}
static void arrayEqual(Object[] x, Object[] y) {
if (x == null ? y == null : Arrays.equals(x, y)) pass();
else fail(Arrays.toString(x) + " not equal to " + Arrays.toString(y));}
public static void main(String[] args) throws Throwable {
try {realMain(args);} catch (Throwable t) {unexpected(t);}
System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
if (failed > 0) throw new AssertionError("Some tests failed");}
private static abstract class Fun {abstract void f() throws Throwable;}
static void THROWS(Class<? extends Throwable> k, Fun... fs) {
for (Fun f : fs)
try { f.f(); fail("Expected " + k.getName() + " not thrown"); }
catch (Throwable t) {
if (k.isAssignableFrom(t.getClass())) pass();
else unexpected(t);}}
private static abstract class CheckedThread extends Thread {
abstract void realRun() throws Throwable;
public void run() {
try {realRun();} catch (Throwable t) {unexpected(t);}}}
}