/*

 * Copyright (c) 2014, 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;

class AllocateBeyondMetaspaceSize {

  public static Object dummy;

  public static void main(String [] args) {

    if (args.length != 2) {

      throw new IllegalArgumentException("Usage: <MetaspaceSize> <YoungGenSize>");

    }

    long metaspaceSize = Long.parseLong(args[0]);

    long youngGenSize = Long.parseLong(args[1]);

    run(metaspaceSize, youngGenSize);

  }

  private static void run(long metaspaceSize, long youngGenSize) {

    WhiteBox wb = WhiteBox.getWhiteBox();

    long allocationBeyondMetaspaceSize  = metaspaceSize * 2;

    long metaspace = wb.allocateMetaspace(null, allocationBeyondMetaspaceSize);

    triggerYoungGC(youngGenSize);

    wb.freeMetaspace(null, metaspace, metaspace);

  }

  private static void triggerYoungGC(long youngGenSize) {

    long approxAllocSize = 32 * 1024;

    long numAllocations  = 2 * youngGenSize / approxAllocSize;

    for (long i = 0; i < numAllocations; i++) {

      dummy = new byte[(int)approxAllocSize];

    }

  }

}