joeq is a Java 2 (JDK 1.3 and 1.4) compatible virtual machine. It is unique in that it is entirely implemented in Java, leading to greater reliability, portability, maintainability, and efficiency. It is also language-independent, so code from any supported language can be seamlessly compiled, linked, and executed dynamically.
Classfile Reader & Writer is a Java package that makes it easy to read and write Java class files. It does not provide any help with displaying the contents of a class file (besides debug output) or disassembe the byte codes, but can read "obfuscated" class files such as those generated by Crema.