/*

 * Copyright (c) 2013, 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.management.ManagementFactory;

import java.lang.management.RuntimeMXBean;

import java.lang.reflect.Field;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.List;

import sun.management.VMManagement;

public class JMapHProfLargeHeapProc {

    private static final List<byte[]> heapGarbage = new ArrayList<>();

    public static void main(String[] args) throws Exception {

        buildLargeHeap(args);

        // Print our pid on stdout

        System.out.println("PID[" + getProcessId() + "]");

        // Wait for input before termination

        System.in.read();

    }

    private static void buildLargeHeap(String[] args) {

        for (long i = 0; i < Integer.parseInt(args[0]); i++) {

            heapGarbage.add(new byte[1024]);

        }

    }

    public static int getProcessId() throws Exception {

        // Get the current process id using a reflection hack

        RuntimeMXBean runtime = ManagementFactory.getRuntimeMXBean();

        Field jvm = runtime.getClass().getDeclaredField("jvm");

        jvm.setAccessible(true);

        VMManagement mgmt = (sun.management.VMManagement) jvm.get(runtime);

        Method pid_method = mgmt.getClass().getDeclaredMethod("getProcessId");

        pid_method.setAccessible(true);

        int pid = (Integer) pid_method.invoke(mgmt);

        return pid;

    }

}