Whereas the remote-procedure-call (RPC) abstraction, including its derivates such as remote method invocation, has proven to be an adequate programming paradigm for client-server applications over LANs, type-based publish-subscribe (TPS) is an appealing candidate programming abstraction for decoupled and completely decentralized applications that run over large-scale and mobile networks. TPS enforces type safety and encapsulation (just like RPC) while providing decoupling and scalability properties (unlike RPC).

Two TPS implementations in Java demonstrate this approach’s potential. The first is a seminal approach relying on specific primitives added to the Java language. The second is a library implementation based on more general recent Java mechanisms, avoiding any specific compilation.