Solved

how do i get instance count of an java object?

Posted on 2003-12-01
8
1,562 Views
Last Modified: 2012-06-27
how do i get instance count of an object.
since i want to free memory. i can set an reference to null.
but if there are other references to the same object garbage collector
won't free the memory. i want to explicitly set all references to that
object to null. how do i do that?
0
Comment
Question by:sharath_kulal
8 Comments
 
LVL 4

Accepted Solution

by:
vk33 earned 20 total points
ID: 9848820
afaik, it's the matter of specific JVM implementation. You can only manipulate stored links.
0
 
LVL 92

Assisted Solution

by:objects
objects earned 20 total points
ID: 9848821
you can't. best you can is (and all you really need to do) is make sure you set any references to null when they are no longer needed.
0
 
LVL 15

Assisted Solution

by:jimmack
jimmack earned 20 total points
ID: 9848830
Besides that, in the circumstances you describe, an instance count wouldn't help.  Multiple references to a single object would not affect a count of instances.
0
Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

 
LVL 35

Expert Comment

by:TimYates
ID: 9848909
I think they meant reference count ;-)
0
 
LVL 7

Assisted Solution

by:grim_toaster
grim_toaster earned 20 total points
ID: 9848919
If you're really concerned about memory, I would suggest getting hold of a memory profiler.  One that I would recommend is JProbe (you can download a trial version), but the only problem with it is that it is not a free product!

http://java.quest.com/jprobe/
0
 
LVL 35

Assisted Solution

by:TimYates
TimYates earned 20 total points
ID: 9848931
OptimizeIt is an ok profiler too :-)

You do need to do some investigation as to whether something is a leak, or normal behaviour, as with GC being non-deterministic, it can get a bit tricky ;-)

Memory profiling was so much easier with malloc, calloc, and free ;-)

http://www.borland.com/optimizeit/
0

Featured Post

Announcing the Most Valuable Experts of 2016

MVEs are more concerned with the satisfaction of those they help than with the considerable points they can earn. They are the types of people you feel privileged to call colleagues. Join us in honoring this amazing group of Experts.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Apps blocked by Java 9 88
servlet example 11 49
Bot application - advice 3 38
collection output issue 9 37
For beginner Java programmers or at least those new to the Eclipse IDE, the following tutorial will show some (four) ways in which you can import your Java projects to your Eclipse workbench. Introduction While learning Java can be done with…
Introduction This article is the first of three articles that explain why and how the Experts Exchange QA Team does test automation for our web site. This article explains our test automation goals. Then rationale is given for the tools we use to a…
Viewers learn about the third conditional statement “else if” and use it in an example program. Then additional information about conditional statements is provided, covering the topic thoroughly. Viewers learn about the third conditional statement …
Viewers will learn about basic arrays, how to declare them, and how to use them. Introduction and definition: Declare an array and cover the syntax of declaring them: Initialize every index in the created array: Example/Features of a basic arr…

837 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question