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/*
* Copyright (c) 2015, 2017, 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 sun.hotspot.WhiteBox;
public class LockStringTest extends Thread {
static String lock = "StringLock";
static boolean done = false;
public static void main(String[] args) throws Exception {
WhiteBox wb = WhiteBox.getWhiteBox();
if (wb.areSharedStringsIgnored()) {
System.out.println("The shared strings are ignored");
System.out.println("LockStringTest: PASS");
return;
}
if (!wb.isShared(lock)) {
throw new RuntimeException("Failed: String is not shared.");
}
new LockStringTest().start();
synchronized(lock) {
while (!done) {
lock.wait();
}
}
System.gc();
System.out.println("LockStringTest: PASS");
}
public void run() {
String shared = "LiveOak";
synchronized (lock) {
for (int i = 0; i < 100; i++) {
new String(shared);
System.gc();
try {
sleep(5);
} catch (InterruptedException e) {}
}
done = true;
lock.notify();
}
}
}
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