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/*
* Copyright (c) 2001, 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 Verify that concurrent class descriptor lookups function properly,
* even when class descriptor initialization is slow or throws an
* exception.
*/
import java.io.*;
class Good implements Serializable {
static {
try { Thread.sleep(1000); } catch (InterruptedException ex) {}
}
}
class Bad implements Serializable {
// explicit suid triggers class initialization during classdesc lookup
private static final long serialVersionUID = 0xBAD;
static {
try { Thread.sleep(1000); } catch (InterruptedException ex) {}
if ("foo".equals("foo")) {
throw new RuntimeException();
}
}
}
class SuccessfulLookup extends Thread {
Class cl;
long suid;
Object barrier;
boolean ok;
SuccessfulLookup(Class cl, long suid, Object barrier) {
this.cl = cl;
this.suid = suid;
this.barrier = barrier;
}
public void run() {
synchronized (barrier) {
try { barrier.wait(); } catch (InterruptedException ex) {}
}
for (int i = 0; i < 100; i++) {
if (ObjectStreamClass.lookup(cl).getSerialVersionUID() != suid) {
return;
}
}
ok = true;
}
}
class FailingLookup extends Thread {
Class cl;
Object barrier;
boolean ok;
FailingLookup(Class cl, Object barrier) {
this.cl = cl;
this.barrier = barrier;
}
public void run() {
synchronized (barrier) {
try { barrier.wait(); } catch (InterruptedException ex) {}
}
for (int i = 0; i < 100; i++) {
try {
ObjectStreamClass.lookup(cl);
return;
} catch (Throwable th) {
}
}
ok = true;
}
}
public class ConcurrentClassDescLookup {
public static void main(String[] args) throws Exception {
ClassLoader loader = ConcurrentClassDescLookup.class.getClassLoader();
Class cl = Class.forName("Good", false, loader);
Object barrier = new Object();
SuccessfulLookup[] slookups = new SuccessfulLookup[50];
for (int i = 0; i < slookups.length; i++) {
slookups[i] =
new SuccessfulLookup(cl, 6319710844400051132L, barrier);
slookups[i].start();
}
Thread.sleep(1000);
synchronized (barrier) {
barrier.notifyAll();
}
for (int i = 0; i < slookups.length; i++) {
slookups[i].join();
if (!slookups[i].ok) {
throw new Error();
}
}
cl = Class.forName("Bad", false, loader);
FailingLookup[] flookups = new FailingLookup[50];
for (int i = 0; i < flookups.length; i++) {
flookups[i] = new FailingLookup(cl, barrier);
flookups[i].start();
}
Thread.sleep(1000);
synchronized (barrier) {
barrier.notifyAll();
}
for (int i = 0; i < slookups.length; i++) {
flookups[i].join();
if (!flookups[i].ok) {
throw new Error();
}
}
}
}
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