1 /*
   2 * Copyright (c) 2013, 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  * @test TestG1HeapRegionSize
  26  * @key gc
  27  * @bug 8021879
  28  * @summary Verify that the flag G1HeapRegionSize is updated properly
  29  * @run main/othervm -XX:+UseG1GC -Xmx64m TestG1HeapRegionSize 1048576
  30  * @run main/othervm -XX:+UseG1GC -XX:G1HeapRegionSize=2m -Xmx64m TestG1HeapRegionSize 2097152
  31  * @run main/othervm -XX:+UseG1GC -XX:G1HeapRegionSize=3m -Xmx64m TestG1HeapRegionSize 2097152
  32  */
  33 
  34 import sun.management.ManagementFactoryHelper;
  35 import com.sun.management.HotSpotDiagnosticMXBean;
  36 import com.sun.management.VMOption;
  37 
  38 public class TestG1HeapRegionSize {
  39 
  40   public static void main(String[] args) {
  41     String expectedValue = getExpectedValue(args);
  42     HotSpotDiagnosticMXBean diagnostic = ManagementFactoryHelper.getDiagnosticMXBean();
  43     VMOption option = diagnostic.getVMOption("G1HeapRegionSize");
  44     if (!expectedValue.equals(option.getValue())) {
  45       throw new RuntimeException("Wrong value for G1HeapRegionSize. Expected " + expectedValue + " but got " + option.getValue());
  46     }
  47   }
  48 
  49   private static String getExpectedValue(String[] args) {
  50     if (args.length != 1) {
  51       throw new RuntimeException("Wrong number of arguments. Expected 1 but got " + args.length);
  52     }
  53     return args[0];
  54   }
  55 
  56 }