Languages for the Java VM - A list of tools for programming to the Java virtual machine using a language other than Java itself. (Robert Tolksdorf)
List of Java compilers - A list of both source-code-to-bytecode and bytecode-to-native compilers, including an introductory article on native compilers and alternatives.
Jasmin - A Java bytecode assembler. [Open Source, GPL]
The KOPI Project - Java compiler, byte-code assembler, disassembler. [Open Source, GPL]
Jikes - IBM Research Jikes Compiler Project. A Java compiler written in C++. [Open Source, IBM Public License]
Harissa - Java environment that includes a compiler from Java bytecode to C and a Java interpreter. [Open Source, GPL]
Java(tm) Bytecode Assembler - Free, but for research and educational use only.
Applet Servlet - Free online compiler and runner for Java applets.
DJ - Java decompiler and editor for Windows. [Freeware]
