| Along with the computer networks going deeper into people's life, work and study, the advanced applications in the enterprises, such as the electronic commerce, are becoming a kind of strong impetus and causing a series of new concepts, new techniques and new products among which application server is the most conspicuous one. At the same time, the government is gradually developing the electronic governmental affairs management, realizing the information sharing, opening the governmental affairs management, and providing the services. The various complicated application systems involve many complicated application environment, operating system platforms and databases. And they also relate to the high level requirements such as complicated logical calculation, distributed application deployment, gradually and sectionally implementation. Consequently, application server is necessary for establishing a uniform platform of performance and deployment. In addition, considering the serious problems such as the national information security and so on, the application server with the independent Chinese copyright will be the first choice in the areas such as establishing system of the electronic government affairs.Supported by the National High Technology Development 863 Program of China and the National Grand Fundamental Research 973 Program of China, Institute of Software, Chinese Academy of Sciences has developed an application server named as Webframe, which is following the J2EE1.3 specification presented by Sun Microsystems Inc. Webframe Application Server is a standard J2EE application server, supporting various operating systems and various database platforms. It may work as the enterprise distributed computing platform with multi-business logic, high flexibility and high reliability, which is suitable for electronic commerce, electronics governmental affairs, financial institutions, etc.The J2EE specification, presented by Sun Microsystems Inc, is a systemic specification based on Java2 platform for simplifying the enterprise solution of development, deployment and management. The J2EE platform is based on J2SE platform, the standard version of Java2 platform. It adopts many advantages of the standard version and comprehensively supports various techniques like EJB, Java Servlet, JSP, JNDI, JDBC, JTA and JMS, etc.This paper introduces following two aspects of the work that the auther has engagedin Webframe application server project.As a subject of Webframe application server project, we have designed and implemented Web Container of Webframe Application Server. Fully supporting Java Servlet and JSP techniques, it is an advanced extension for web server. In the process of developing Web Container, we follow the Servlet2.3 specification, the JSP 1.2 specification and HTTP 1.1 protocol, apply various of program design techniques, software engineering techniques and some common design patterns based on the Java platform and analyze the functions and software architecture of the Web Container system thoroughly. We design and implement more functions of the Web Container system, including system configuration, security certification, system log, system management and application deployment. Adopting technical concepts of component-based in software engineering, we implement the functions of the models with different software components to make the Web Container system highly extendable and reusable. In addition we also study the key techniques in implementing the Web Container system such as translation of JSP files, secure connection management and session management.Based on the Web Container system, we have designed and implemented the cluster of Web Container, including implementation of the algorithms for defining the manager of the cluster and for calculating the groups of the cluster. We also have designed and implemented a HTTP reverse proxy server with load balancing, session binding and fail-over, etc, which increase the ability of request responding and fault-tolerant. In the HTTP rev...
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