how to make flowChart of java source code in NetBeans

Hello Friends,

Currently I am working on an open source Software. I wanna modify it, I have its source code in java. But source code is very complicated infact lengthy. Can any one guide me how to make flow chart of available code so that I could understand it properly. I am using NetBeans ver 7.2.

1. Is this option available in netBeans
2. Is there any software availabe for such type of requirement.
3. Do any one have any hint for me.

Can you use one of the automated tools which create UML diagrams?
Who wrote the long and complicated code? You or somebody else?

Problem solved. But help was not encourging.

solution is available at
http://java.ittoolbox.com/groups/technical-functional/java-l/how-to-make-flowchart-from-java-source-1423394