Go - Oct 2, 1997
metaXa - A meta architecture for the JavaTM virtual machine (MetaJava)
The metaXa project is discontinued. The experiences we gained during the metaXa project flow in our current project JX: The Flexible Operating System Architecture
Overview
Increasing complexity of hardware architectures and the accompanying increased complexity of modern software are creating challenging demands to the flexibility and adaptability of runtime support and operating systems.General purpose architectures often cannot fulfil special requirements of applications or are providing only less optimal solutions. Therefore new software architectures are needed, which provide mechanisms for a cooperation between applications and an adaptable and extendable runtime or operating system. The Java architecture is a big step in the right direction but the step is not big enough.
We extended Java with a reflective metalevel architecture. Reflection is the capability of a system to reason about and act upon its own computation and adjust itself to changing conditions. Metaprogramming separates the adjusting mechanisms from the functionality of the program. It is even possible to formulate the metaprogram in a generic way and use it for arbitrary objects.
Applications
- A tracing metaobject that is able to trace method invocations, instance variable accesses, lock accesses, and object instantiations.
- A replicating metaobject that manages consistency of replicated objects. RepliXa
- A metaobject that translates Java bytecode into native machine code.
Publications and Reports
The metaXa design and prototype were developed in the context of Michael Golm's Diplomarbeit (masters thesis).