I found that the Jad eclipse plug-in is a good java decompiler.
The version I use is Jad v1.5.8g. Copyright 2001 Pavel Kouznetsov.
It can decompile in two ways:
1) in the Project Explorer, open the jar file and navigate to the class files. this only applies to OOTB jars.
2) from a java file, right click on a class and click open declaration.
If you try to open a .class file. it will show the following error:
/*jadclipse*/
//Error!
http://stackoverflow.com/questions/6736435/problem-while-setting-jad-with-eclipse-helios
