【正文】 cremental service deployments depending on the needs of the application allow for most efficient utilization of server resources. There are several J2EE application servers that are already fully or partially ponentized, including open source application servers JBoss [11] and JOnAS [19]. We feel that dynamic reconfiguration of application servers through dynamic deployment and undeployment of system services is essential to building a resourceefficient framework for dynamic distributed deployment of J2EE applications. Therefore we advocate and will use as a model a microkernel application server design used by the JBoss application server [8]. In this model a minimal server consists of a service invocation bus, a robust classloading subsystem, some naming subsystem and a dynamic deployment subsystem. All other services are hotdeployable and municate through a mon invocation bus. For example, JBoss utilizes a Java Management Extensions (JMX) [27] server that provides basic naming and invocation facilities. In addition JBoss implements an advanced classloading subsystem and a deployment service. All other JBoss services are dynamically deployable and expose themselves as JMX MBeans with well defined (un)deployment mechanism and lifecycle. Such an application server design facilitates explicit handling of application ponent dependencies on system services and proper configuration and deployment of only required system services. References [1] Apache Software Foundation. Apache Geronimo Application Server. [2] N. Arshad, D. Heimbigner, and A. L. Wolf. Deployment and dynamic reconfiguration planning for distributed software systems. In Proceedings of the 15th International Conference on Tools with Artificial Intelligence (ICTAI’03), November 2020. [3] T. Batista and N. Rodriguez. Dynamic reconfiguration of ponentbased applications. In Proceedings of the International Symposium on Software Engineering for Parallel and Distributed Systems, June 2020. [4] BEA Systems Inc. WebLogic Application Server. [5] G. Candea, E. Kiciman, S. Zhang, P. Keyani, and A. Fox. JAGR: An autonomous selfrecovering application server. In Proceedings of the 5th International Workshop on Active Middleware Services, June 2020. [6] M. Chen, E. Kiciman, E. Fratkin, E. Brewer, and A. Fox. Pinpoint: Problem determination in large, dynamic, Inter services. In Proceedings of the International Conference on Dependable Systems and Networks, June 2020. [7] J. E. Cook and J. A. Dage. Highly reliable upgrading of ponents. In Proceedings of the 21st International Conference on Software Engineering (ICSE’99), May 1999. [8] M. Fleury and F. Reverbel. The JBoss extensible server. In Proceedings of the ACM/IFIP/USENIX International Middleware Conference (Middleware’2020), June 2020. [9] IBM Corporation. WebSphere Application Server. [10] Java Community Process. Java Specification Request 88 (JSR88). [11] JBoss Group. JBoss Application Server. [12] T. Kichkaylo, A. Ivan, and V. Karamcheti. Constrained ponent deployment in widearea works using AI planning techniques. In Proceedings of the International Parallel and Distributed Processing Symposium (IPDPS), April 2020. [13] F. Kon and R. H. Campbell. Dependence management in ponentbased distributed systems. IEEE Concurrency, 8(1):26–36, 2020. [14] D. Llambiri, A. Totok, and V. Karamcheti. Efficiently distributing ponentbased applications across widearea environments. In Proceedings of the International Conference on Distributed Computing Systems (ICDCS), pages 412–421, May 2020. [15] , A. Tseng, and J. Kramer. Composing distributed objects in CORBA. In Proceedings of the Third International Symposium on Autonomous Decentralized Systems (ISADS’97), pages 257–263, 1997. [16] V. Marangozova and D. Hagimont. An infrastructure for CORBA ponent replication. In Proceedings of the IFIP/ACM Working Conference on Component Deployment, pages 257–263, 2020. [17] Microsoft Corporation. Microsoft .NET. [18] Object Management Group. CORBA Component Model (CCM) Specification. [19] ObjectWeb Consortium. JOnAS Application Server. [20] ObjectWeb Consortium. RUBiS: Rice University Bidding System. [21] Oracle Corporation. Oracle Application Server. [22] M. Rutherford, K. Anderson, A. Carzaniga, D. Heimbigner, and A. . Reconfiguration in the Enterprise JavaBean ponent model. In Proceedings of the IFIP/ACM Working Conference on Component Deployment, pages 67–81, 2020. [23] Sun Microsystems Inc. Java Pet Store Sample Application. [24] Sun Microsystems Inc. Enterprise JavaBeans (EJB) Specification. [25] Sun Microsystems Inc. Java 2 Enterprise Edition. [26] Sun Microsystems Inc. Java Connector Architecture (JCA) Specification. [27] Sun Microsystems Inc. Java Management Extensions (JMX) Specification. [28] Sun Microsystems Inc. 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[34] XmlBlaster Open Source Project. 附錄 2 外文翻譯 基于 J2EE在分布式環(huán)境下的底層結(jié)構(gòu)自動動態(tài)部署應(yīng)用 Anatoly Akkerman, Alexander Totok, and Vijay Karamcheti 摘要： 為了實現(xiàn)其動態(tài)的可適應(yīng)性，我們需要一種框架來在廣域網(wǎng)中符合工業(yè)標準基于組件的環(huán)境里自動化地配置 J2EE 應(yīng)用程序。 (2) 廣域垂直層需要復(fù)制應(yīng)用層組件而且需要維持和原組件間的一致性。在需要跨越多個節(jié)點服務(wù)器的廣域網(wǎng)配置中，這將更加復(fù)雜，因為更多的便捷內(nèi)部節(jié)點通信的系統(tǒng)服務(wù)需要配置和啟動，比如 IP地址，端口號， JNDI名字和其他的數(shù)據(jù)在多個節(jié)點的配置文件中必須維持一致性。這種組件說明語言用來描述應(yīng)用程序組件和鏈接。這種架構(gòu)實現(xiàn)利用了 JBoss的可擴展的微內(nèi)核結(jié)構(gòu)，基于 JMX規(guī)范。 組件框架是一種中間件系統(tǒng)，支持遵守一定標準的有不同組件構(gòu)成的應(yīng)用程序。 (3) 服務(wù)器提供給組件的服務(wù)。服務(wù)器端包括 Java Servlet 組件、 Java 服務(wù)器頁面（ jsp）和靜態(tài)網(wǎng)頁內(nèi)容。它們在調(diào)用樣式（同步和異步，本地和遠程）與狀態(tài)：完全狀態(tài)（如 MDB）， 不可持久狀態(tài)（如 SSB），可持久狀態(tài)（如 EB）等