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/*
* Copyright (c) 2016, 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.
*/
package optionsvalidation;
import java.lang.ref.WeakReference;
class JVMStartup {
private static volatile WeakReference<Object> weakRef;
private static synchronized void createWeakRef() {
Object o = new Object();
weakRef = new WeakReference<>(o);
}
/* Simple method to test that java start-up. Used for testing options. */
public static void main(String[] args) throws Exception {
byte[] garbage = new byte[8192];
int i = 0;
createWeakRef();
do {
garbage = new byte[8192];
i++;
/* Initiate GC after 5 iterations */
if (i > 5) {
System.gc();
}
} while(weakRef.get() != null);
System.out.println("Java start-up!");
}
}
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