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/*
* Copyright (c) 2018, 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 8201793
* @summary Test Reference::clone to throw CloneNotSupportedException
*/
import java.lang.ref.*;
public class ReferenceClone {
private static final ReferenceQueue<Object> QUEUE = new ReferenceQueue<>();
public static void main(String... args) {
ReferenceClone refClone = new ReferenceClone();
refClone.test();
}
public void test() {
// test Reference::clone that throws CNSE
Object o = new Object();
assertCloneNotSupported(new SoftRef(o));
assertCloneNotSupported(new WeakRef(o));
assertCloneNotSupported(new PhantomRef(o));
// Reference subclass may override the clone method
CloneableReference ref = new CloneableReference(o);
try {
ref.clone();
} catch (CloneNotSupportedException e) {}
}
private void assertCloneNotSupported(CloneableRef ref) {
try {
ref.clone();
throw new RuntimeException("Reference::clone should throw CloneNotSupportedException");
} catch (CloneNotSupportedException e) {}
}
// override clone to be public that throws CNSE
interface CloneableRef extends Cloneable {
public Object clone() throws CloneNotSupportedException;
}
class SoftRef extends SoftReference<Object> implements CloneableRef {
public SoftRef(Object referent) {
super(referent, QUEUE);
}
public Object clone() throws CloneNotSupportedException {
return super.clone();
}
}
class WeakRef extends WeakReference<Object> implements CloneableRef {
public WeakRef(Object referent) {
super(referent, QUEUE);
}
public Object clone() throws CloneNotSupportedException {
return super.clone();
}
}
class PhantomRef extends PhantomReference<Object> implements CloneableRef {
public PhantomRef(Object referent) {
super(referent, QUEUE);
}
public Object clone() throws CloneNotSupportedException {
return super.clone();
}
}
// override clone to return a new instance
class CloneableReference extends WeakReference<Object> implements Cloneable {
public CloneableReference(Object referent) {
super(referent, QUEUE);
}
public Object clone() throws CloneNotSupportedException {
return new CloneableReference(this.get());
}
}
}
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