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/*
* Copyright (c) 2005, 2015, 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 5086470 6358247
* @summary Basic Test for ThreadMXBean.dumpAllThreads(false, true)
* and getThreadInfo of customized JSR-166 synchronizers.
* @author Mandy Chung
*
* @build Barrier
* @build ThreadDump
* @run main/othervm MyOwnSynchronizer
*/
import java.lang.management.*;
import java.util.*;
import java.util.concurrent.locks.*;
import java.util.concurrent.TimeUnit;
import java.io.*;
public class MyOwnSynchronizer {
static ThreadMXBean mbean = ManagementFactory.getThreadMXBean();
static Mutex mutex = new Mutex();
static MyThread thread = new MyThread();
public static void main(String[] argv) throws Exception {
if (!mbean.isSynchronizerUsageSupported()) {
System.out.println("Monitoring of synchronizer usage not supported");
return;
}
thread.setDaemon(true);
thread.start();
// wait until myThread acquires mutex
while (!mutex.isLocked()) {
try {
Thread.sleep(100);
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
ThreadDump.threadDump();
// Test dumpAllThreads with locked synchronizers
ThreadInfo[] tinfos = mbean.dumpAllThreads(false, true);
for (ThreadInfo ti : tinfos) {
MonitorInfo[] monitors = ti.getLockedMonitors();
if (monitors.length != 0) {
throw new RuntimeException("Name: " + ti.getThreadName() +
" has non-empty locked monitors = " + monitors.length);
}
LockInfo[] syncs = ti.getLockedSynchronizers();
if (ti.getThreadId() == thread.getId()) {
thread.checkLockedSyncs(ti, syncs);
}
}
// Test getThreadInfo with locked synchronizers
tinfos = mbean.getThreadInfo(new long[] {thread.getId()}, false, true);
if (tinfos.length != 1) {
throw new RuntimeException("getThreadInfo() returns " +
tinfos.length + " ThreadInfo objects. Expected 0.");
}
ThreadInfo ti = tinfos[0];
if (ti.getLockedMonitors().length != 0) {
throw new RuntimeException("Name: " + ti.getThreadName() +
" has non-empty locked monitors = " +
ti.getLockedMonitors().length);
}
thread.checkLockedSyncs(ti, ti.getLockedSynchronizers());
System.out.println("Test passed");
}
static class Mutex implements Lock, java.io.Serializable {
// Our internal helper class
class Sync extends AbstractQueuedSynchronizer {
// Report whether in locked state
protected boolean isHeldExclusively() {
return getState() == 1;
}
// Acquire the lock if state is zero
public boolean tryAcquire(int acquires) {
assert acquires == 1; // Otherwise unused
if (compareAndSetState(0, 1)) {
setExclusiveOwnerThread(Thread.currentThread());
return true;
}
return false;
}
// Release the lock by setting state to zero
protected boolean tryRelease(int releases) {
assert releases == 1; // Otherwise unused
if (getState() == 0) throw new IllegalMonitorStateException();
setExclusiveOwnerThread(null);
setState(0);
return true;
}
// Provide a Condition
Condition newCondition() { return new ConditionObject(); }
// Deserialize properly
private void readObject(ObjectInputStream s)
throws IOException, ClassNotFoundException {
s.defaultReadObject();
setState(0); // reset to unlocked state
}
}
// The sync object does all the hard work. We just forward to it.
private final Sync sync = new Sync();
public void lock() { sync.acquire(1); }
public boolean tryLock() { return sync.tryAcquire(1); }
public void unlock() { sync.release(1); }
public Condition newCondition() { return sync.newCondition(); }
public boolean isLocked() { return sync.isHeldExclusively(); }
public boolean hasQueuedThreads() { return sync.hasQueuedThreads(); }
public void lockInterruptibly() throws InterruptedException {
sync.acquireInterruptibly(1);
}
public boolean tryLock(long timeout, TimeUnit unit) throws InterruptedException {
return sync.tryAcquireNanos(1, unit.toNanos(timeout));
}
public AbstractOwnableSynchronizer getSync() { return sync; }
}
static class MyThread extends Thread {
public MyThread() {
super("MyThread");
}
public void run() {
mutex.lock();
Object o = new Object();
synchronized(o) {
try {
o.wait();
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
}
int OWNED_SYNCS = 1;
void checkLockedSyncs(ThreadInfo info, LockInfo[] syncs) {
if (!getName().equals(info.getThreadName())) {
throw new RuntimeException("Name: " + info.getThreadName() +
" not matched. Expected: " + getName());
}
if (syncs.length != OWNED_SYNCS) {
throw new RuntimeException("Number of locked syncs = " +
syncs.length +
" not matched. Expected: " + OWNED_SYNCS);
}
AbstractOwnableSynchronizer s = mutex.getSync();
String lockName = s.getClass().getName();
int hcode = System.identityHashCode(s);
if (!lockName.equals(syncs[0].getClassName())) {
throw new RuntimeException("LockInfo : " + syncs[0] +
" class name not matched. Expected: " + lockName);
}
if (hcode != syncs[0].getIdentityHashCode()) {
throw new RuntimeException("LockInfo: " + syncs[0] +
" IdentityHashCode not matched. Expected: " + hcode);
}
}
}
}
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