Howto determine Object size in memory?

Question

HI there!
I know the JVM has a function which prints out a list of all obejcts currently instantiated with the object size and the number how many objects of this type are alive, but I dont know anymore howto enable this feature.
My Profiler does not show this information :-(
Any ideas?
Thanks in advance, lgClemens

Answer 1

Read in another thread that you coudl do like this:
  public static long calculateMemoryUsage(ObjectFactory factory) {
    System.gc(); System.gc(); System.gc(); System.gc();
    System.gc(); System.gc(); System.gc(); System.gc();
    System.gc(); System.gc(); System.gc(); System.gc();
    System.gc(); System.gc(); System.gc(); System.gc();
    long mem0 = Runtime.getRuntime().totalMemory() -
      Runtime.getRuntime().freeMemory();
    Object handle = factory.makeObject();
    System.gc(); System.gc(); System.gc(); System.gc();
    System.gc(); System.gc(); System.gc(); System.gc();
    System.gc(); System.gc(); System.gc(); System.gc();
    System.gc(); System.gc(); System.gc(); System.gc();
    long mem1 = Runtime.getRuntime().totalMemory() -
      Runtime.getRuntime().freeMemory();
    return mem1 - mem0;
public interface ObjectFactory {
  public Object makeObject();
}Gil