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/*
* Copyright (c) 2002, 2011, 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 4625907
* @summary Testing force()
* @run main/othervm Force
* @key randomness
*/
import java.io.*;
import java.nio.*;
import java.util.*;
import java.nio.channels.*;
public class Force {
public static void main(String[] args) throws Exception {
Random random = new Random();
long filesize = random.nextInt(3*1024*1024);
int cut = random.nextInt((int)filesize);
File file = File.createTempFile("Blah", null);
file.deleteOnExit();
try (RandomAccessFile raf = new RandomAccessFile(file, "rw")) {
raf.setLength(filesize);
FileChannel fc = raf.getChannel();
MappedByteBuffer mbb = fc.map(FileChannel.MapMode.READ_WRITE, cut, filesize-cut);
mbb.force();
}
// improve chance that mapped buffer will be unmapped
System.gc();
Thread.sleep(500);
}
}
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