java使用java.lang.management监视和管理 Java 虚拟机

软件包 java.lang.management

提供管理接口，用于监视和管理 Java 虚拟机以及 Java 虚拟机在其上运行的操作系统。

 

接口摘要

ClassLoadingMXBean	用于 Java 虚拟机的类加载系统的管理接口。
CompilationMXBean	用于 Java 虚拟机的编译系统的管理接口。
GarbageCollectorMXBean	用于 Java 虚拟机的垃圾回收的管理接口。
MemoryManagerMXBean	内存管理器的管理接口。
MemoryMXBean	Java 虚拟机的内存系统的管理接口。
MemoryPoolMXBean	内存池的管理接口。
OperatingSystemMXBean	用于操作系统的管理接口，Java 虚拟机在此操作系统上运行。
RuntimeMXBean	Java 虚拟机的运行时系统的管理接口。
ThreadMXBean	Java 虚拟机线程系统的管理接口。

 import java.lang.management.ClassLoadingMXBean;
 import java.lang.management.CompilationMXBean;
 import java.lang.management.GarbageCollectorMXBean;
 import java.lang.management.ManagementFactory;
 import java.lang.management.MemoryMXBean;
 import java.lang.management.MemoryManagerMXBean;
 import java.lang.management.MemoryPoolMXBean;
 import java.lang.management.MemoryUsage;
 import java.lang.management.OperatingSystemMXBean;
 import java.lang.management.RuntimeMXBean;
 import java.lang.management.ThreadMXBean;
 import java.util.List;

 import javax.management.MBeanServerConnection;

 public class MBeanDemo {

     public static void main(String[] args) {

         showJvmInfo();
         showMemoryInfo();
         showSystem();
         showClassLoading();
         showCompilation();
         showThread();
         showGarbageCollector();
         showMemoryManager();
         showMemoryPool();
     }

     /**
      * Java 虚拟机的运行时系统
      */
     public static void showJvmInfo() {
         RuntimeMXBean mxbean = ManagementFactory.getRuntimeMXBean();
         String vendor = mxbean.getVmVendor();
         System.out.println("jvm name:" + mxbean.getVmName());
         System.out.println("jvm version:" + mxbean.getVmVersion());
         System.out.println("jvm bootClassPath:" + mxbean.getBootClassPath());
         System.out.println("jvm start time:" + mxbean.getStartTime());
     }

     /**
      * Java 虚拟机的内存系统
      */
     public static void showMemoryInfo() {
         MemoryMXBean mem = ManagementFactory.getMemoryMXBean();
         MemoryUsage heap = mem.getHeapMemoryUsage();
         System.out.println("Heap committed:" + heap.getCommitted() + " init:" + heap.getInit() + " max:"
                            + heap.getMax() + " used:" + heap.getUsed());
     }

     /**
      * Java 虚拟机在其上运行的操作系统
      */
     public static void showSystem() {
         OperatingSystemMXBean op = ManagementFactory.getOperatingSystemMXBean();
         System.out.println("Architecture: " + op.getArch());
         System.out.println("Processors: " + op.getAvailableProcessors());
         System.out.println("System name: " + op.getName());
         System.out.println("System version: " + op.getVersion());
         System.out.println("Last minute load: " + op.getSystemLoadAverage());
     }

     /**
      * Java 虚拟机的类加载系统
      */
     public static void showClassLoading(){
         ClassLoadingMXBean cl = ManagementFactory.getClassLoadingMXBean();
         System.out.println("TotalLoadedClassCount: " + cl.getTotalLoadedClassCount());
         System.out.println("LoadedClassCount" + cl.getLoadedClassCount());
         System.out.println("UnloadedClassCount:" + cl.getUnloadedClassCount());
     }

     /**
      * Java 虚拟机的编译系统
      */
     public static void showCompilation(){
         CompilationMXBean com = ManagementFactory.getCompilationMXBean();
         System.out.println("TotalCompilationTime:" + com.getTotalCompilationTime());
         System.out.println("name:" + com.getName());
     }

     /**
      * Java 虚拟机的线程系统
      */
     public static void showThread(){
         ThreadMXBean thread = ManagementFactory.getThreadMXBean();
         System.out.println("ThreadCount" + thread.getThreadCount());
         System.out.println("AllThreadIds:" + thread.getAllThreadIds());
         System.out.println("CurrentThreadUserTime" + thread.getCurrentThreadUserTime());
         //......还有其他很多信息
     }

     /**
      * Java 虚拟机中的垃圾回收器。
      */
     public static void showGarbageCollector(){
         List gc = ManagementFactory.getGarbageCollectorMXBeans();
         for(GarbageCollectorMXBean GarbageCollectorMXBean : gc){
             System.out.println("name:" + GarbageCollectorMXBean.getName());
             System.out.println("CollectionCount:" + GarbageCollectorMXBean.getCollectionCount());
             System.out.println("CollectionTime" + GarbageCollectorMXBean.getCollectionTime());
         }
     }

     /**
      * Java 虚拟机中的内存管理器
      */
     public static void showMemoryManager(){
         List mm = ManagementFactory.getMemoryManagerMXBeans();
         for(MemoryManagerMXBean eachmm: mm){
             System.out.println("name:" + eachmm.getName());
             System.out.println("MemoryPoolNames:" + eachmm.getMemoryPoolNames().toString());
         }
     }

     /**
      * Java 虚拟机中的内存池
      */
     public static void showMemoryPool(){
         List mps = ManagementFactory.getMemoryPoolMXBeans();
         for(MemoryPoolMXBean mp : mps){
             System.out.println("name:" + mp.getName());
             System.out.println("CollectionUsage:" + mp.getCollectionUsage());
             System.out.println("type:" + mp.getType());
         }
     }

     /**
      * 访问 MXBean 的方法的三种方法
      */
     public static void visitMBean(){

         //第一种直接调用同一 Java 虚拟机内的 MXBean 中的方法。
         RuntimeMXBean mxbean = ManagementFactory.getRuntimeMXBean();
         String vendor1 = mxbean.getVmVendor();
         System.out.println("vendor1:" + vendor1);

         //第二种通过一个连接到正在运行的虚拟机的平台 MBeanServer 的 MBeanServerConnection。
         MBeanServerConnection mbs = null;
         // Connect to a running JVM (or itself) and get MBeanServerConnection
         // that has the JVM MXBeans registered in it

         /*
         try {
             // Assuming the RuntimeMXBean has been registered in mbs
             ObjectName oname = new ObjectName(ManagementFactory.RUNTIME_MXBEAN_NAME);
             String vendor2 = (String) mbs.getAttribute(oname, "VmVendor");
             System.out.println("vendor2:" + vendor2);
         } catch (Exception e) {
             e.printStackTrace();
         }
         */

         //第三种使用 MXBean 代理
 //        MBeanServerConnection mbs3 = null;
 //        RuntimeMXBean proxy;
 //        try {
 //            proxy = ManagementFactory.newPlatformMXBeanProxy(mbs3,ManagementFactory.RUNTIME_MXBEAN_NAME,
 //                                                     RuntimeMXBean.class);
 //            String vendor = proxy.getVmVendor();
 //        } catch (IOException e) {
 //            e.printStackTrace();
 //        }

     }

 }

输出：

 jvm name:Java HotSpot(TM) Client VM
 jvm version:1.6.0-b105
 jvm bootClassPath:C:\Program Files\Java\jdk1.6.0\jre\lib\resources.jar;C:\Program Files\Java\jdk1.6.0\jre\lib\rt.jar;C:\Program Files\Java\jdk1.6.0\jre\lib\sunrsasign.jar;C:\Program Files\Java\jdk1.6.0\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.6.0\jre\lib\jce.jar;C:\Program Files\Java\jdk1.6.0\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.6.0\jre\classes
 jvm start time:1307440032774
 Heap committed:5177344 init:0 max:66650112 used:632640
 Architecture: x86
 Processors: 2
 System name: Windows XP
 System version: 5.1
 Last minute load: -1.0
 TotalLoadedClassCount: 381
 LoadedClassCount381
 UnloadedClassCount:0
 TotalCompilationTime:3
 name:HotSpot Client Compiler
 ThreadCount5
 AllThreadIds:[J@47b480
 CurrentThreadUserTime15625000
 name:Copy
 CollectionCount:0
 CollectionTime0
 name:MarkSweepCompact
 CollectionCount:0
 CollectionTime0
 name:CodeCacheManager
 MemoryPoolNames:[Ljava.lang.String;@1389e4
 name:Copy
 MemoryPoolNames:[Ljava.lang.String;@c20e24
 name:MarkSweepCompact
 MemoryPoolNames:[Ljava.lang.String;@2e7263
 name:Code Cache
 CollectionUsage:null
 type:Non-heap memory
 name:Eden Space
 CollectionUsage:init = 917504(896K) used = 0(0K) committed = 0(0K) max = 4194304(4096K)
 type:Heap memory
 name:Survivor Space
 CollectionUsage:init = 65536(64K) used = 0(0K) committed = 0(0K) max = 458752(448K)
 type:Heap memory
 name:Tenured Gen
 CollectionUsage:init = 4194304(4096K) used = 0(0K) committed = 0(0K) max = 61997056(60544K)
 type:Heap memory
 name:Perm Gen
 CollectionUsage:init = 12582912(12288K) used = 0(0K) committed = 0(0K) max = 67108864(65536K)
 type:Non-heap memory
 name:Perm Gen [shared-ro]
 CollectionUsage:init = 8388608(8192K) used = 0(0K) committed = 0(0K) max = 8388608(8192K)
 type:Non-heap memory
 name:Perm Gen [shared-rw]
 CollectionUsage:init = 12582912(12288K) used = 0(0K) committed = 0(0K) max = 12582912(12288K)
 type:Non-heap memory