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/*
* Copyright (c) 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.
*
* 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.
*/
import org.testng.annotations.Test;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CompletionException;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CountDownLatch;
import java.util.function.Supplier;
import java.util.stream.IntStream;
import java.util.stream.Stream;
/**
* @test
* @bug 8028564
* @run testng ConcurrentContainsKeyTest
* @summary Test that entries are always present in the map,
* when entries are held within one bin that is a tree
*/
@Test
public class ConcurrentContainsKeyTest {
// The number of entries for each thread to place in a map
// Should be > ConcurrentHashMap.TREEIFY_THRESHOLD but small
// enough to allow for enough iteration overlap by multiple threads
private static final int N = Integer.getInteger("n", 16);
// The number of rounds each thread performs per entry
private static final int R = Integer.getInteger("r", 32);
// The number of iterations of the test
private static final int I = Integer.getInteger("i", 256);
// Object to be placed in the concurrent map
static class X implements Comparable<X> {
private final int a;
X(int a) {
this.a = a;
}
public int compareTo(X o) {
return this.a - o.a;
}
public int hashCode() {
// Return the same hash code to guarantee collisions
return 0;
}
}
@Test
public void testContainsKey() {
X[] content = IntStream.range(0, N).mapToObj(i -> new X(i)).toArray(X[]::new);
// Create map with an initial size >= ConcurrentHashMap.TREEIFY_THRESHOLD
// ensuring tree'ification will occur for a small number of entries
// with the same hash code
ConcurrentHashMap<Object, Object> m = new ConcurrentHashMap<>(64);
Stream.of(content).forEach(x -> m.put(x, x));
test(content, m);
}
private static void test(X[] content, ConcurrentHashMap<Object, Object> m) {
for (int i = 0; i < I; i++) {
testOnce(content, m);
}
}
static class AssociationFailure extends RuntimeException {
AssociationFailure(String message) {
super(message);
}
}
private static void testOnce(Object[] content, ConcurrentHashMap<Object, Object> m) {
CountDownLatch s = new CountDownLatch(1);
Supplier<Runnable> sr = () -> () -> {
try {
s.await();
}
catch (InterruptedException e) {
}
for (int i = 0; i < R * N; i++) {
Object o = content[i % content.length];
if (!m.containsKey(o)) {
throw new AssociationFailure("CHM.containsKey failed: entry does not exist");
}
}
};
int ps = Runtime.getRuntime().availableProcessors();
Stream<CompletableFuture> runners = IntStream.range(0, ps)
.mapToObj(i -> sr.get())
.map(CompletableFuture::runAsync);
CompletableFuture all = CompletableFuture.allOf(
runners.toArray(CompletableFuture[]::new));
// Trigger the runners to start checking key membership
s.countDown();
try {
all.join();
}
catch (CompletionException e) {
Throwable t = e.getCause();
if (t instanceof AssociationFailure) {
throw (AssociationFailure) t;
}
else {
throw e;
}
}
}
}
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