JAVA代码中获取JVM信息

最新推荐文章于 2024-12-10 20:36:34 发布

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CC 4.0 BY-SA版权

原文链接：https://www.cnblogs.com/songxingzhu/p/9106394.html

文章标签：

#JVM

本文详细介绍了如何使用Java的ManagementFactory类获取JVM的各种信息，包括进程ID、内存使用情况、操作系统信息、线程详情等，为Java开发者提供了深入了解和监控JVM运行状态的方法。

一、JAVA中获取JVM的信息

原理，利用JavaSDK自带的ManagementFactory类来获取。

二、获取信息

1、获取进程ID

@Test
public void test1() {
    RuntimeMXBean mxb = ManagementFactory.getRuntimeMXBean();
    System.out.println(mxb.getName()); //2668@Sindrol-PC
}

2、获取ManagementFactory.getRuntimeMXBean()的其它信息

RuntimeMXBean mxb = ManagementFactory.getRuntimeMXBean();
mxb.getSystemProperties() = {HashMap@866}  size = 56
mxb.getInputArguments() = {Collections$UnmodifiableRandomAccessList@1039}  size = 5
mxb.getBootClassPath() = "C:\Program Files\Java\jdk1.8.0_161\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\rt.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\sunrsasign.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_161\jre\classes;D:\Applicaton\DevTools\JetBrains\IntelliJIDEA\lib\rt\debugger-agent-storage.jar"
mxb.getLibraryPath() = "C:\Program Files\Java\jdk1.8.0_161\bin;C:\windows\Sun\Java\bin;C:\windows\system32;C:\windows;C:\Program Files\Docker\Docker\Resources\bin;C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v8.0\bin;C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v8.0\libnvvp;C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v8.0\lib\x64;D:\Applicaton\DevTools\Python\3.5\Scripts\;D:\Applicaton\DevTools\Python\3.5\;D:\Applicaton\DevTools\cudnn-8.0-windows10-x64-v5.1\cuda;D:\Applicaton\DevTools\cudnn-8.0-windows10-x64-v5.1\cuda\bin;D:\Applicaton\DevTools\cudnn-8.0-windows10-x64-v5.1\cuda\lib\x64;D:\Applicaton\DevTools\cudnn-8.0-windows10-x64-v5.1\cuda\lib;C:\Program Files (x86)\Common Files\NetSarang;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\Microsoft SQL Server\120\Tools\Binn\;C:\Program Files\Microsoft SQL Server\130\Tools\Binn\;C:\Program Files\Microsoft\Web Platform Installer\;C:\Program Files (x86)\Microsoft SDKs\Azure\CL"
mxb.getClassPath() = "D:\Applicaton\DevTools\JetBrains\IntelliJIDEA\lib\idea_rt.jar;D:\Applicaton\DevTools\JetBrains\IntelliJIDEA\plugins\junit\lib\junit-rt.jar;D:\Applicaton\DevTools\JetBrains\IntelliJIDEA\plugins\junit\lib\junit5-rt.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_161\jre\lib\ext\sunpkcs11.jar;C:\Pr"
mxb.getManagementSpecVersion() = "1.2"
mxb.getSpecName() = "Java Virtual Machine Specification"
mxb.getSpecVendor() = "Oracle Corporation"
mxb.getStartTime() = 1527587462275
mxb.getUptime() = 95372
mxb.getVmVendor() = "Oracle Corporation"
mxb.getObjectName() = {ObjectName@1052} "java.lang:type=Runtime"
mxb.getName() = "2668@Sindrol-NTB"

3、获取操作系统信息

@Test
public void test2() {
	OperatingSystemMXBean osb = ManagementFactory.getOperatingSystemMXBean();
	System.out.println(osb.getName()); //Windows 10
	System.out.println(osb.getArch()); //amd 64
	System.out.println(osb.getAvailableProcessors()); //4
	System.out.println(osb.getVersion()); //10.0
	System.out.println(osb.getSystemLoadAverage()); //-1.0
}

4、获取JVM的内存

@Test
public void test4() {
	MemoryMXBean mxb = ManagementFactory.getMemoryMXBean();
	//Heap
	System.out.println("Max:" + mxb.getHeapMemoryUsage().getMax() / 1024 / 1024 + "MB");    //Max:1776MB
	System.out.println("Init:" + mxb.getHeapMemoryUsage().getInit() / 1024 / 1024 + "MB");  //Init:126MB
	System.out.println("Committed:" + mxb.getHeapMemoryUsage().getCommitted() / 1024 / 1024 + "MB");   //Committed:121MB
	System.out.println("Used:" + mxb.getHeapMemoryUsage().getUsed() / 1024 / 1024 + "MB");  //Used:7MB
	System.out.println(mxb.getHeapMemoryUsage().toString());    //init = 132120576(129024K) used = 8076528(7887K) committed = 126877696(123904K) max = 1862270976(1818624K)
	
	//Non heap
	System.out.println("Max:" + mxb.getNonHeapMemoryUsage().getMax() / 1024 / 1024 + "MB");    //Max:0MB
	System.out.println("Init:" + mxb.getNonHeapMemoryUsage().getInit() / 1024 / 1024 + "MB");  //Init:2MB
	System.out.println("Committed:" + mxb.getNonHeapMemoryUsage().getCommitted() / 1024 / 1024 + "MB");   //Committed:8MB
	System.out.println("Used:" + mxb.getNonHeapMemoryUsage().getUsed() / 1024 / 1024 + "MB");  //Used:7MB
	System.out.println(mxb.getNonHeapMemoryUsage().toString());    //init = 2555904(2496K) used = 7802056(7619K) committed = 9109504(8896K) max = -1(-1K)
}

5、获取JVM的内存池情况

@Test
public void test5() {
    List<MemoryPoolMXBean> mxb = ManagementFactory.getMemoryPoolMXBeans();
    for (MemoryPoolMXBean memoryPoolMXBean : mxb) {
        System.out.println("Name:" + memoryPoolMXBean.getName());
        System.out.println("Usage:" + memoryPoolMXBean.getUsage());
        System.out.println("Manager:" + String.join(",", memoryPoolMXBean.getMemoryManagerNames()));
        System.out.println("Type:" + memoryPoolMXBean.getType());
        System.out.println("--------------------------");
    }

}

结果：

Name:Code Cache
Usage:init = 2555904(2496K) used = 1742656(1701K) committed = 2555904(2496K) max = 251658240(245760K)
Manager:CodeCacheManager
Type:Non-heap memory
--------------------------
Name:Metaspace
Usage:init = 0(0K) used = 5436960(5309K) committed = 5767168(5632K) max = -1(-1K)
Manager:Metaspace Manager
Type:Non-heap memory
--------------------------
Name:Compressed Class Space
Usage:init = 0(0K) used = 632000(617K) committed = 786432(768K) max = 1073741824(1048576K)
Manager:Metaspace Manager
Type:Non-heap memory
--------------------------
Name:PS Eden Space
Usage:init = 33554432(32768K) used = 8076056(7886K) committed = 33554432(32768K) max = 687865856(671744K)
Manager:PS MarkSweep,PS Scavenge
Type:Heap memory
--------------------------
Name:PS Survivor Space
Usage:init = 5242880(5120K) used = 0(0K) committed = 5242880(5120K) max = 5242880(5120K)
Manager:PS MarkSweep,PS Scavenge
Type:Heap memory
--------------------------
Name:PS Old Gen
Usage:init = 88080384(86016K) used = 0(0K) committed = 88080384(86016K) max = 1396703232(1363968K)
Manager:PS MarkSweep
Type:Heap memory
--------------------------

6、获取程序线程信息

@Test
public void test6() {
    ThreadMXBean tmx = ManagementFactory.getThreadMXBean();
    System.out.println("thread count:" + tmx.getThreadCount());
    for (long id : tmx.getAllThreadIds()) {
        ThreadInfo ti = tmx.getThreadInfo(id);
        System.out.println(ti.toString().trim());
        System.out.println("cpu time:" + tmx.getThreadCpuTime(id));
        System.out.println("user time:" + tmx.getThreadUserTime(id));
        System.out.println("-----------------");
    }
    System.out.println("findDeadlockedThreads:");
    if (tmx.findDeadlockedThreads() != null)
        for (long id : tmx.findDeadlockedThreads()) {
            ThreadInfo ti = tmx.getThreadInfo(id);
            System.out.println(ti.toString().trim());
        }
}

结果：

thread count:6
"Monitor Ctrl-Break" Id=6 RUNNABLE (in native)
cpu time:0
user time:0
-----------------
"Attach Listener" Id=5 RUNNABLE
cpu time:0
user time:0
-----------------
"Signal Dispatcher" Id=4 RUNNABLE
cpu time:0
user time:0
-----------------
"Finalizer" Id=3 WAITING on java.lang.ref.ReferenceQueue$Lock@22927a81
cpu time:0
user time:0
-----------------
"Reference Handler" Id=2 WAITING on java.lang.ref.Reference$Lock@78e03bb5
cpu time:0
user time:0
-----------------
"main" Id=1 RUNNABLE
cpu time:203125000
user time:171875000
-----------------
findDeadlockedThreads: