How to check memory usage by java program?

Question

Is there any native Java code to check the memory used by the program, or is the only way to check the memory used by the itlself JVM?
can this be done exclusively in java or do we need an external process to do this work?

Answer 1

I think JConsole would be a good start.

Answer 2

You can use java.lang.management.MemoryUsageeither the external VisualVM tool (supplied with the JDK).

Answer 3

java.lang.management.MemoryMXBean , MemoryUsage. , , :

MemoryMXBean memoryBean = ManagementFactory.getMemoryMXBean();
long heapMemUsed = memoryBean.getHeapMemoryUsage().getUsed();
long otherMemUsed = memoryBean.getNonHeapMemoryUsage().getUsed();
long totalMemoryUsed = heapMemUsed + otherMemUsed;

Answer 4

Is there something that jConsole cannot provide? It shows heaps, classes, threads, processor, and more.