如何确定我的Java程序消耗了多少内存

Question

I have a class as follows:

class MyClass
{
 public static void main(String args[])
 {
  //I want statistics here
 }
}

Any help would be appreciated.

Answer 1

Runtime runtime = Runtime.getRuntime();

NumberFormat format = NumberFormat.getInstance();

StringBuilder sb = new StringBuilder();
long maxMemory = runtime.maxMemory();
long allocatedMemory = runtime.totalMemory();
long freeMemory = runtime.freeMemory();

sb.append("free memory: " + format.format(freeMemory / 1024) + "<br/>");
sb.append("allocated memory: " + format.format(allocatedMemory / 1024) + "<br/>");
sb.append("max memory: " + format.format(maxMemory / 1024) + "<br/>");
sb.append("total free memory: " + format.format((freeMemory + (maxMemory - allocatedMemory)) / 1024) + "<br/>");

Answer 2

The MemoryMXBean has all the memory data available. This includes data about both heap and non heap memory. The Runtime class only provides access to information about heap memory.