- Protecting the Ideas Behind Your Code
- Obfuscation As a Protection of Intellectual Property
- Transformations Performed by Obfuscators
- Knowing the Best Obfuscators
- Potential Problems and Common Solutions
- Using Zelix KlassMaster to Obfuscate a Chat Application
- Cracking Obfuscated Code
- Quick Quiz
- In Brief
Obfuscation As a Protection of Intellectual Property
Obfuscation is the process of transforming bytecode to a less human-readable form with the purpose of complicating reverse engineering. It typically includes stripping out all the debug information, such as variable tables and line numbers, and renaming packages, classes, and methods to machine-generated names. Advanced obfuscators go further and change the control flow of Java code by restructuring the existing logic and inserting bogus code that will not execute. The premise of the obfuscation is that the transformations do not break the validity of the bytecode and do not alter the exposed functionality.
Obfuscation is possible for the same reasons that decompiling is possible: Java bytecode is standardized and well documented. Obfuscators load Java class files, parse their formats, and then apply transformations based on supported features. When all the transformations are applied, the bytecode is saved as a new class file. The new file has a different internal structure but behaves just like the original file.