Migration of a Chosen Architectural Pattern to Service Oriented ...

Chapter 3. Architectural Patterns 72from the scratch with usage of Java Struts framework. The framework providesbuild-in support for MVC pattern. Other approach for MVC-SOA integrationproposes changes in MVC pattern. More explicitly, it adapts MMVC pattern toSOA architecture [67] and focuses on data transfer part of the desktop application.The solution proposes introduction of an additional broker component andpublisher-subscriber design pattern for communication. The other approach suggestscollaboration of services with model part of MVC [28]. Model simply bindsand invokes previously found in registry services. The services become externalresources like database. Studies on MVC and SOA include also integration fromGUI point of view [78].Client–ServerClient–Server is an architectural pattern that due to its nature is used in distributedsystems therefore a special interest from SOA related researches mightbe expected. The studies exist and in fact are in advances phase. They do notconsider only possibilities of migration but provide also a prototype frameworkautomating migration from Client-Server legacy application into SOA application[36]. The framework solves problem of migration of VB.Net application bywrapping their code into web services but other languages are also considered asa feature work. Other studies consider performance of SOA applications based onClient–Server pattern and compare it to SOA applications based on Peer–to–Peerpattern [26].Half–Sync / Half–AsyncNo information about Half–Sync / Half–Async and its integration with / migrationto SOA was found.3.4.2 Pattern for migrationFilter 7: Final selectionConsidering information gathered during prefeasibility study, three patterns haveincreased probability of successful migration. The increased feasibility is a resultof already conducted studies related to those patterns and SOA. However, thestudies present the patterns as worthy further consideration, only one can bechosen. Client–Serverpattern is rejected due to advances phase of studies relatedto SOA and migration, while Pipe–and–Filters appears in the context of EnterpriseApplication Integration only. Additionally, Pipes–and–Filters is consideredonly in one study. Model View Controller is the pattern that is analysed frommany perspectives but does not exist in the context of migration. The pattern isalso widely supported by many frameworks which are not restricted to one languagebut rather are a bias of existing languages including Java (Spring, Struts)