JAVA打印堆转储

Question

I work with Java 1.7 and I want to print Heap Dump from java

...
Object heapDump=.... ;
...

System.out.println(heapDump);

Can anybody help me?

Answer 1

Use jmap :

jmap -dump:format=b,file=heap.bin <pid>

refer to Java 7 jmap tutorial .

Answer 2

您可以使用HotSpotDiagnosticMXBean以编程方式创建堆转储。

Answer 3

You can't print the Heap Dump directly using SOP Statement. But you can dump all the data in a file. JVM will create heap dump every time when your application throws an OutOfMemoryError . HeapDumpPath is used to set location of heap dumps.

We can also use jmap from our code. Assume name,pid are the fileds retrieving. To get a pid from code use we need to use java.lang.management.ManagementFactory .

String name = ManagementFactory.getRuntimeMXBean().getName();
String pid = name.substring(0, name.indexOf("@"));
After that we can start jmap process like this:
String[] cmd = { "jmap", "-dump:file=D:\\temp\\heapdumps\\dump.bin", pid };
Process p = Runtime.getRuntime().exec(cmd);