The most worried things in java world is how to save your code from decoding.
As you all know that there are certain tools which decode or convert your .class file code to .java files.
So how can you save your code.Solution is make a exe or Executable for windows user.
If you want for window OS then here i am listing all the tool for converting jar files to exe Executable.
These tools are also used for deployment purpose or setup maker.
I used many of them and they are superb.
11. Advace Installer