1 /*

     2  * Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  *

    23  */

    24 

    25 import sun.hotspot.WhiteBox;

    26 

    27 // This class should be loaded from a shared archive.

    28 public class MultiProcClass {

    29     private static String instanceLabel;

    30 

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

    32         instanceLabel = args[0];

    33         String checkPmap = args[1];

    34 

    35         long pid = ProcessHandle.current().pid();

    36         System.out.println(inst("========================== Starting MultiProcClass"));

    37         System.out.println(inst("My PID: " + pid ));

    38         System.out.println(inst("checkPmap = <" + checkPmap + ">" ));

    39 

    40         if ("true".equals(checkPmap)) {

    41             if (runPmap(pid, true) != 0)

    42                 System.out.println("MultiProcClass: Pmap failed");

    43         }

    44 

    45         WhiteBox wb = WhiteBox.getWhiteBox();

    46         if (!wb.isSharedClass(MultiProcClass.class)) {

    47             throw new RuntimeException(inst("MultiProcClass should be shared but is not."));

    48         }

    49 

    50         System.out.println(inst("========================== Leaving MultiProcClass"));

    51     }

    52 

    53     // A convenience method to append process instance label

    54     private static String inst(String msg) {

    55         return "process-" + instanceLabel + " : " + msg;

    56     }

    57 

    58     // Use on Linux-only; requires jdk-9 for Process.pid()

    59     public static int runPmap(long pid, boolean inheritIO) throws Exception {

    60         ProcessBuilder pmapPb = new ProcessBuilder("pmap", "" + pid);

    61         if (inheritIO)

    62             pmapPb.inheritIO();

    63 

    64         return pmapPb.start().waitFor();

    65     }

    66 }