DJ - Support for adaptive programming (dynamic structure-shy traversals and visitors) in pure Java. Aspect Browser - A tool for Java (with optional Emacs support) which helps developers to find and visualise crosscutting concerns, using text matching. [Freeware] DemeterJ - An adaptive programming language based on Java. The "big sister" of DJ. Macker - Helps enforce architectural rules (layering, tiering, and modularity) in Java code. It applies pattern-based access rules from XML rules files to compiled classes. [Open source, GPL] AspectJ - Aspect-oriented Java extension, seamless, from Xerox PARC. Goal: to make aspect-oriented programming (AOP) technology available to a wide range of programmers. [Open Source, MPL] EAOP tool - A research prototype for Event-based Aspect-Oriented Programming (EAOP) for Java. ASM - Very small and fast Java bytecode manipulation framework; can be used to dynamically generate stub classes or other proxy classes, directly in binary form, or to dynamically modify classes at load time, just before loaded into a JVM. [Open Source, BSD] PROSE - PROgrammable extenSions of sErvices; allows modifying Java programs at run-time; dynamic aspect-oriented programming (AOP), adaptive service architectures, and information systems for mobile computing. JAsCo - Advanced Java-based aspect-oriented programming (AOP or AOSD) language originally tailored for the component-based field. Main traits: highly reusable aspects, strong aspectual composition mechanism to manage combinations of aspects.