How to make a Java Program unextractable

Question

Sorry I am not very sure how to state the question title. My problem is like this, I had developed a Java program, and I wish to distribute it to my friends. So I export it to Jar file, but I don't want them to extract the jar file to view the code. Is there anyway to make the program so that nobody can get the source code instead just launch the program.

Answer 1

You can always get the original code back from compiled class files. However, you can make the lives of those who wish to decompile such code very difficult by using an obfuscator, so the decompiled code is nearly impossible to read. Here is a list of open-source java obfuscators which you might wish to investigate.

Answer 2

If a computer can run it, a human can reverse engineer it.