1 /*
   2  * Copyright (c) 2020, 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 TestMemoryManagerMXBean
  26  * @requires vm.gc.Z
  27  * @summary Test ZGC memory manager MXBean
  28  * @modules java.management
  29  * @run main/othervm -XX:+UseZGC -Xmx128M TestMemoryManagerMXBean
  30  */
  31 
  32 import java.lang.management.ManagementFactory;
  33 
  34 public class TestMemoryManagerMXBean {
  35     private static void checkName(String name) throws Exception {
  36         if (name == null || name.length() == 0) {
  37             throw new Exception("Invalid name");
  38         }
  39     }
  40 
  41     public static void main(String[] args) throws Exception {
  42         int zgcMemoryManagers = 0;
  43         int zgcMemoryPools = 0;
  44 
  45         for (final var memoryManager : ManagementFactory.getMemoryManagerMXBeans()) {
  46             final var memoryManagerName = memoryManager.getName();
  47             checkName(memoryManagerName);
  48 
  49             System.out.println("MemoryManager: " + memoryManagerName);
  50 
  51             if (memoryManagerName.equals("ZGC")) {
  52                 zgcMemoryManagers++;
  53             }
  54 
  55             for (final var memoryPoolName : memoryManager.getMemoryPoolNames()) {
  56                 checkName(memoryPoolName);
  57 
  58                 System.out.println("   MemoryPool:   " + memoryPoolName);
  59 
  60                 if (memoryPoolName.equals("ZHeap")) {
  61                     zgcMemoryPools++;
  62                 }
  63             }
  64 
  65             if (zgcMemoryManagers != zgcMemoryPools) {
  66                 throw new Exception("MemoryManagers/MemoryPools mismatch");
  67             }
  68         }
  69 
  70         if (zgcMemoryManagers != 1) {
  71             throw new Exception("All MemoryManagers not found");
  72         }
  73 
  74         if (zgcMemoryPools != 1) {
  75             throw new Exception("All MemoryPools not found");
  76         }
  77     }
  78 }