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/*
* Copyright (c) 1997, 2012, 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
* @summary Basic functional test of reference objects
* @author Mark Reinhold
*/
import java.lang.ref.*;
import java.util.Vector;
public class Basic {
static ReferenceQueue q = new ReferenceQueue();
static ReferenceQueue q2 = new ReferenceQueue();
static Reference rw, rw2, rp, rp2;
static Vector keep = new Vector();
static boolean finalized = false;
public static class ClearFinalizerThread {
protected void finalize() {
System.err.println("Cleared finalizer thread");
}
};
protected void finalize() {
Basic.finalized = true;
System.err.println("Finalized " + this);
}
public static class Sub { };
Object sub = new Sub();
static void fork(Runnable proc) throws InterruptedException {
Thread t = new Thread(proc);
t.start();
t.join();
}
static void showReferences() throws InterruptedException {
fork(new Runnable() {
public void run() {
System.err.println("References: W " + rw.get()
+ ", W2 " + rw2.get()
+ ", P " + rp.get()
+ ", P2 " + rp2.get());
}
});
}
static void createNoise() throws InterruptedException {
fork(new Runnable() {
public void run() {
keep.addElement(new PhantomReference(new Object(), q2));
}
});
}
public static void main(String[] args) throws Exception {
fork(new Runnable() {
public void run() {
Basic s = new Basic();
rw = new WeakReference(s, q);
rw2 = new WeakReference(s);
rp = new PhantomReference(s, q);
rp2 = new PhantomReference(s.sub, q);
s = null;
}
});
showReferences();
int ndq = 0;
boolean prevFinalized = false;
outer:
for (int i = 1;; i++) {
Reference r;
createNoise();
System.err.println("GC " + i);
Thread.sleep(10);
System.gc();
System.runFinalization();
showReferences();
while ((r = q2.poll()) != null) {
System.err.println("Noise " + r);
}
/* Cause a dummy object to be finalized, since the finalizer thread
might retain a reference to the Basic instance after it's been
finalized (this happens with java_g) */
if (Basic.finalized && !prevFinalized) {
fork(new Runnable() {
public void run() {
new ClearFinalizerThread();
}});
prevFinalized = true;
}
while ((r = q.poll()) != null) {
ndq++;
if (r != null) {
System.err.println("Dequeued " + r);
if (ndq == 3) break outer;
}
}
if (i >= 10) break;
}
if (ndq != 3) {
throw new Exception("Expected to dequeue 3 reference objects,"
+ " but only got " + ndq);
}
if (! Basic.finalized) {
throw new Exception("Test object not finalized");
}
}
}
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