Using Design Patterns and Frameworks to Develop Object-Oriented Communication Systems

Factory 19 Tactical Patterns Proxy { \Provide a surrogate or placeholder for another object to control access to it" Strategy { \De ne a family of algorithms, encapsulate each one, and make them interchangeable" Adapter { \Convert the interface of a class into another interface client expects" Singleton { \Ensure a class only has one instance and provide a global point of access to it" State { \Allow an object to alter its behavior when its internal state changes" 20 Event Handling Patterns Reactor { \Decouples synchronous event demultiplexing and event handler initiation dispatching from service(s) performed in response to events" Proactor { \Decouples asynchronous event demultiplexing and event handler completion dispatching from service(s) performed in response to events" Asynchronous Completion Token { \E ciently associates state with the completion of asynchronous operations" 21 Concurrency Patterns Active Object { \Decouples method execution from method invocation and simpli es synchronized access to shared resources by concurrent threads" Half-Sync/Half-Async { \Decouples synchronous I/O from asynchronous I/O in a system to simplify concurrent programming e ort without degrading execution e ciency" Double-Checked Locking Optimization Pattern { \Ensures atomic initialization of objects and eliminates unnecessary locking overhead on each access"