LbusFrame-A Lightweight Business Service Layer Framework

Object-oriented technology, delegated by J2EE, has demonstrated its value in a multitude of enterprise applications around the industry. However, traditional J2EE orthodoxy makes heavy work for simple problems, results in over-designed J2EE applications. Applications builder should not design source pooling, thread management, service lookup, data access, and more important business layer framework. Some simple approaches to developing J2EE applications emerge. Among those approaches, building a business layer framework, which is described in this thesis, presents an alternate access. LbusFrame framework, is introduced throughout with core requirements, detailed analysis principles, package descriptions, UML diagrams, and code fragments.An typical J2EE application has multi-tiers architecture, namely data access layer, presentation layer, and our focus, business services layer. Business services layer is the center of application. Presentation layer, mainly with MVC pattern, operates user interfaces and remote facades. And data access layer, with typical DAO pattern, manipulates persistence store.Our approach to business service layer is based on composite pattern and strategy pattern. Business model means all entities which should be found in the conceptual view of the business, from which we can extract domain model, which consists of only those entities that are of interest to the user and relationships among them. Domain model provides user interface for presentation layer, while business model applies business facades to communicate with DAOs from data access layer. Within business service layer, there are nothing else except entities and relationships among them. To manipulate, such as create, read, update and delete those relationships, LbusFrame adopts composite classes and leaf classes, both derived from abstract component class. Being subclass of one class, composite class and leaf class delegate basic units to build "nets-shapes" architecture, and resultant units hold unidirectionality or bidirectionality of entity relationships. On the roadmap, Lbusframe will provides resource lookup facility, resolving dependencies managed objects by implementing Inversion of Control (IOC).Despite of those entities and their relationships, with wiring algorithms to "algorithm class", Lbusframe has ability of composing several algorithm to one and depriving algorithm form anther. Gears with strategy pattern, Lbusframe can load or unload algorithms dynamically at runtime.