j2se 5.0使用 Java Management Extensions (JMX)来管理和监控java平台。
我们以一个例子来测试一下:
import java.lang.management.ClassLoadingMXBean; import java.lang.management.CompilationMXBean; import java.lang.management.ManagementFactory; import java.lang.management.MemoryMXBean; import java.lang.management.MemoryManagerMXBean; import java.lang.management.MemoryPoolMXBean; import java.lang.management.OperatingSystemMXBean; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.List; public class JDKMBean { public static <T> void printMXBean(Class<T> t,Object object) { Method[] methods = t.getMethods(); T instance = (T)object; System.out.printf("%n---%s---%n", t.getName()); for(Method m:methods) { if (m.getName().startsWith("get")) { try { Object rtValue = m.invoke(instance,new Object[0]); System.out.printf("%s:%s%n",m.getName().substring(3),rtValue); } catch (IllegalArgumentException e1) { } catch (IllegalAccessException e) { } catch (InvocationTargetException e) { } } } } public static <T> void printMXBeans(Class<T> t,List<T> list) { for(T bean:list) { printMXBean(t,bean); } } public static void main(String[] args) { JDKMBean.printMXBean(OperatingSystemMXBean.class,ManagementFactory.getOperatingSystemMXBean()); JDKMBean.printMXBean(CompilationMXBean.class,ManagementFactory.getCompilationMXBean()); JDKMBean.printMXBean(ClassLoadingMXBean.class,ManagementFactory.getClassLoadingMXBean()); JDKMBean.printMXBean(MemoryMXBean.class,ManagementFactory.getMemoryMXBean()); JDKMBean.printMXBeans(MemoryManagerMXBean.class,ManagementFactory.getMemoryManagerMXBeans()); JDKMBean.printMXBeans(MemoryPoolMXBean.class,ManagementFactory.getMemoryPoolMXBeans()); } }
运行结果:
---java.lang.management.OperatingSystemMXBean---
Arch:x86
AvailableProcessors:2
Name:Windows 2000
Version:5.0
---java.lang.management.CompilationMXBean---
TotalCompilationTime:5
Name:HotSpot Client Compiler
---java.lang.management.ClassLoadingMXBean---
LoadedClassCount:431
UnloadedClassCount:0
TotalLoadedClassCount:431
---java.lang.management.MemoryMXBean---
HeapMemoryUsage:init = 0(0K) used = 458288(447K) committed = 2031616(1984K) max = 66650112(65088K)
NonHeapMemoryUsage:init = 29556736(28864K) used = 12541248(12247K) committed = 29851648(29152K) max = 121634816(118784K)
ObjectPendingFinalizationCount:0
---java.lang.management.MemoryManagerMXBean---
MemoryPoolNames:[Ljava.lang.String;@6ca1c
Name:CodeCacheManager
---java.lang.management.MemoryManagerMXBean---
MemoryPoolNames:[Ljava.lang.String;@1bf216a
Name:Copy
---java.lang.management.MemoryManagerMXBean---
MemoryPoolNames:[Ljava.lang.String;@12ac982
Name:MarkSweepCompact
---java.lang.management.MemoryPoolMXBean---
CollectionUsage:null
MemoryManagerNames:[Ljava.lang.String;@c20e24
PeakUsage:init = 196608(192K) used = 482048(470K) committed = 491520(480K) max = 33554432(32768K)
Usage:init = 196608(192K) used = 524352(512K) committed = 557056(544K) max = 33554432(32768K)
UsageThreshold:0
UsageThresholdCount:0
Name:Code Cache
Type:Non-heap memory
---java.lang.management.MemoryPoolMXBean---
CollectionUsage:init = 524288(512K) used = 0(0K) committed = 0(0K) max = 4194304(4096K)
CollectionUsageThreshold:0
CollectionUsageThresholdCount:0
MemoryManagerNames:[Ljava.lang.String;@2e7263
PeakUsage:init = 524288(512K) used = 511160(499K) committed = 524288(512K) max = 4194304(4096K)
Usage:init = 524288(512K) used = 521688(509K) committed = 524288(512K) max = 4194304(4096K)
Name:Eden Space
Type:Heap memory
---java.lang.management.MemoryPoolMXBean---
CollectionUsage:init = 65536(64K) used = 0(0K) committed = 0(0K) max = 458752(448K)
CollectionUsageThreshold:0
CollectionUsageThresholdCount:0
MemoryManagerNames:[Ljava.lang.String;@157f0dc
PeakUsage:init = 65536(64K) used = 65528(63K) committed = 65536(64K) max = 458752(448K)
Usage:init = 65536(64K) used = 65528(63K) committed = 65536(64K) max = 458752(448K)
Name:Survivor Space
Type:Heap memory
---java.lang.management.MemoryPoolMXBean---
CollectionUsage:init = 1441792(1408K) used = 0(0K) committed = 0(0K) max = 61997056(60544K)
CollectionUsageThreshold:0
CollectionUsageThresholdCount:0
MemoryManagerNames:[Ljava.lang.String;@863399
PeakUsage:init = 1441792(1408K) used = 142120(138K) committed = 1441792(1408K) max = 61997056(60544K)
Usage:init = 1441792(1408K) used = 142120(138K) committed = 1441792(1408K) max = 61997056(60544K)
UsageThreshold:0
UsageThresholdCount:0
Name:Tenured Gen
Type:Heap memory
---java.lang.management.MemoryPoolMXBean---
CollectionUsage:init = 8388608(8192K) used = 0(0K) committed = 0(0K) max = 67108864(65536K)
CollectionUsageThreshold:0
CollectionUsageThresholdCount:0
MemoryManagerNames:[Ljava.lang.String;@a59698
PeakUsage:init = 8388608(8192K) used = 641040(626K) committed = 8388608(8192K) max = 67108864(65536K)
Usage:init = 8388608(8192K) used = 641040(626K) committed = 8388608(8192K) max = 67108864(65536K)
UsageThreshold:0
UsageThresholdCount:0
Name:Perm Gen
Type:Non-heap memory
---java.lang.management.MemoryPoolMXBean---
CollectionUsage:init = 8388608(8192K) used = 0(0K) committed = 0(0K) max = 8388608(8192K)
CollectionUsageThreshold:0
CollectionUsageThresholdCount:0
MemoryManagerNames:[Ljava.lang.String;@141d683
PeakUsage:init = 8388608(8192K) used = 5601632(5470K) committed = 8388608(8192K) max = 8388608(8192K)
Usage:init = 8388608(8192K) used = 5601632(5470K) committed = 8388608(8192K) max = 8388608(8192K)
UsageThreshold:0
UsageThresholdCount:0
Name:Perm Gen [shared-ro]
Type:Non-heap memory
---java.lang.management.MemoryPoolMXBean---
CollectionUsage:init = 12582912(12288K) used = 0(0K) committed = 0(0K) max = 12582912(12288K)
CollectionUsageThreshold:0
CollectionUsageThresholdCount:0
MemoryManagerNames:[Ljava.lang.String;@16a55fa
PeakUsage:init = 12582912(12288K) used = 5850024(5712K) committed = 12582912(12288K) max = 12582912(12288K)
Usage:init = 12582912(12288K) used = 5850024(5712K) committed = 12582912(12288K) max = 12582912(12288K)
UsageThreshold:0
UsageThresholdCount:0
Name:Perm Gen [shared-rw]
Type:Non-heap memory
