Java Security

Hi ,

I would like to know how I can protect my java source code and application ( class files ) from reverser engineering and decompilation softwares.

In fact I want two add 2 feature to my application .
1. I want to sell my application base on license and security file which don`t allow people copy to other system or web host and use it .

I really don`t have idea how i can do it , could you please guide me in this task .

2. I would like to do my class bytecode obfuscator and shrinker to protect my application and not allow people decompile with software or etc .

I try to search on Google and found some different application and way for obfuscator and shrinker but I really don`t know which one is the best one and can protect better and easy to use as well .


Many Many Thanks