The Research And Application Of Open Source ESB-ServiceMix

The ESB has come to various vendors' attention, including middleware,application server and the integration products providers all talk about it.The emergence of ESB, is a highlight in the middleware and integrationfield. Lots of vendors have released their products or plans about it. Butthere was not a open standard for various vendor until the JBI specificationis released. The open source organizations also are developing their ESBproduct. Celtix is hosted ObjectWeb, which is base on IONA's Artix.ServiceMix is developed by LogicBlaze, Gluecode, MortBay and others.It's a incubator project under Apache.This article is along with the thread of SOA-ESB-JBI, introduces SOA,ESB ,JBI and the open ESB-ServiceMix. Then analyzing a concrete case,which integrated two web system base on ServiceMix.When the software system is changing more and more complex, moreand more huge, moreover requires distributed and heterotypic systems caninteroperation well. So the SOA is emerging. The SOA approach is notopposite to the object-oriented, but is to the higher level development,. Inthe process-oriented software, program = data + algorithm;In theobject-oriented software, the program may regard as by each kind of objectto be composed, but object = data + algorithm. In the SOA software, mayregard as by each kind of service and the control flow of these services iscomposed.There is a new solution for the system integration because theemergence of enterprise service bus. The ESB's emergence also provide anew approach for implemented SOA at the same time. The end-to-endinvocation which is a common way in the initial period of SOAdevelopment is changed. The BPEL engine or other services orchestrationtools may be integrated into the enterprise service bus, enables the serviceconsumer to be possible to consume a group of services;Also may integratethe module on the enterprise service bus which business processes,processes including long life cycle each kind of business.At present in the SOA domain each kind of technology, the solution,the product and the standard all unceasingly emerge. The goal of JBIspecification is providing an open standard for the ESB product. Thisspecification describes a messages model, and the message routing, thefoundation services which ESB provides, the interfaces of ESB, and so on.There is a tendency of ESB integrated with the application server. At present,ServiceMix can be integrated with Geronimo, JBoss, and the JOnASapplication server. But Sun Corporation 's ESB product Open -ESB willintegrate to Sun's next generation application server GlassFish. And theJ2EE specification will reference the JBI specification in the future.In this article case, there are two systems which integrated both is theweb system, and only can access these systems via theirs presentation levelinterfaces. At present, still did not have such binding module to be possibleto select, therefore needed to such a binding which can communication withhttp and do transformation between html text and the Normalized Message.So this binding needs to have some common functions with a browser.Based on the http protocol communication, analysis to the html text, andmaintenance the session between the client and the server, at the same time,but also requests the user and the visit proxy is one-one map in this case.In this article, analysis the JBI component which can be deployed onServiceMix. The JBI Component is divided into two different type, theservice engine and binding component. While according to the differentapproach of development and the deployment, there are two differentcomponent type in the servicemix, the lightweight component and thestandard JBI component. The lightweight component development is simple,but relies on ServiceMix itself;The standard component development iscomplex, but may deploy any ESB which support or be compliant JBIspecification.The problems how to communication with multiple target systems andhow to integrate the web page is solved successfully in the case. As well assolve how maintains the session between the client and the server. Thesolution of this case suits the scene that the target web system's presentationisn't changed, and the system only accept the accessing via its presentationlevel interface. This kind of solution does not affect by the integrated systemindependent running, and does not do any change on the integrated system.But the integration base on presentation will relies on target system'ssurface, the coupling is strong. In future if there might be graphic editiontools and automatic generation tools for editing and generating the proxy,this solution may be applied in many scenes, but it only is a feasible solutionat present.