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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 java.lang.reflect.*;
import sun.hotspot.WhiteBox;
/*
* Lock the 'value' field of a known shared string, java.lang.Object
*/
public class LockStringValueTest {
public static void main(String args[]) {
String s = "LiveOak";
WhiteBox wb = WhiteBox.getWhiteBox();
if (wb.areSharedStringsIgnored()) {
System.out.println("The shared strings are ignored");
System.out.println("LockStringValueTest: PASS");
return;
}
if (!wb.isShared(s)) {
throw new RuntimeException("LockStringValueTest Failed: String is not shared.");
}
Class c = s.getClass();
try {
Field f = c.getDeclaredField("value");
f.setAccessible(true);
Object v = f.get(s);
lock(v);
} catch (NoSuchFieldException nfe) {
} catch (IllegalAccessException iae) {}
}
public static void lock(Object o) {
synchronized (o) {
System.out.println("LockStringValueTest: PASS");
}
}
}
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