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Question of the Week Archive

Topic:  Analysis Tools

Question:   Memory inspection/leak detectors

I am observing a lot of memory being consumed in my application (abnormally). Is there any tool that will allow me to view a list of objects that have not been garbage collected? Is there any other way to track this? I have tried outputting messages to System.out through the finalize() method in the classes, but that is just too tedious as I am dealing with a fairly large application.

Thanks.

Answer:  

I have found the Heap Analysis Tool to be invaluable for tracking down problems of this type because it allows you to view the objects that haven't been freed and allows you to find out where the references to them are.

http://developer.java.sun.com/developer/earlyAccess/hat/

Many thanks to JDC member gyrefalcon for contributing to this answer.

Feedback from other JDC members

Tue Apr 06 13:40:57 PDT 1999
Ddunliu
Good!

Wed Apr 07 00:50:18 PDT 1999
gaute
Is there a version of this tool or similar for 1.1?

Wed Apr 07 22:29:12 PDT 1999
Anonymous
It is these type of programs that will make Java
and its programmers work quicker and better

Thu Apr 08 09:06:54 PDT 1999
JDSD
In the Applet case if yu are running this with
Netscape you can see thought java console

Thu Apr 08 10:49:42 PDT 1999
Anonymous
HAT (Heap Analysis Tool) is fine if you're using Java 1.2. Otherwise, there are not any free (or Javasoft-provided) options.
I have used OptimizeIt! with great success. Check it out at http://www.optimizeit.com.

David Dabbs

Fri Apr 09 11:15:56 PDT 1999
krajn
Recently i was evaluating JProbe by KL Group, u can try it
to see the memory usage , time, and number of objects created
by each method in your code.

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