...This one has a bit of a different twist, in that it can obfuscate native methods by generating a .h file which #defines the original method names to the obfuscated ones. Built with Apache BCEL.
A suite of Java ClassLoaders that use "load-time reflection" (the modification of bytecodes upon class loading) to extend existing Java classes. It uses the excellent BCEL library (http://bcel.sf.net).
The Byte Code Engineering Library (formerly known as JavaClass) is intended to give users a
convenient possibility to analyze, create, and manipulate (binary) Java class files . Classes are
represented by updatable objects.