Research And Implement Of Messaging Pattern Transformation

Middleware has played an important role in achieving platform independent communication among system components in large system, especially in distributed system. The message-oriented-middleware (i.e, MOM), which follows message queueing and publish/subcribe pattern is becoming increasingly ubiquitous in many industry domains because of its asynchronous and decoupling features. MOM is also becoming distributed with the development of distributing technology. Unfortunately, most of the current mature distributed MOM only support topic-based publish/subcribe pattern. The distributed MOM which support message queueing pattern is very limited. To change this situation, this paper proposes a scheme that uses messaging pattern transformation to implement a distributed message queueing MOM.Considering the great similarity between message queueing and topic-based publish/subcribe pattern and also the transformation cost, in this paper we propose a pattern transformation mechanism to transform topic-based publish/subscribe pattern into message queueing pattern. This mechanism’s practicability is verified by both Petri nets and implementation in real system Apache Hedwig. In this paper, the similarities and differences between message queueing pattern and topic-based publish/subscribe pattern are firstly discussed. Then the design of pattern transformation mechanism and Petri nets verification of the mechanism are both described in detail. Finally, the implementation and test of this mechanism in Apache Hedwig system is provided at the end of this paper. The test results show that the pattern transformation mechanism proposed in this paper is efficient and practicable. The messaging pattern in Hedwig system is successfully transformed from topic-based publish/subscribe to message queueing.