Changes to serve you more quickly Print sections directly from the information center navigation PDF books are provided as a convenience format for easy printing, reading, and offline use. The information center is the official delivery format for IBM Web Sphere Application Server documentation. If you use the Pdf books primarily for convenient printing, it is now easier to print various parts of the information center as needed, quickly and directly from the information center navigation tree To print a section of the information center navigation Hover your cursor over an entry in the information center navigation until the open Quick Menu icon is displayed beside the entry 2. Right-click the icon to display a menu for printing or searching your selected section of the navigation 3. If you select Print this topic and subtopics from the menu, the selected section is launched in a separate browser window as one HTML file. The HTML file includes each of the topics in the section with a table of contents at the top 4. Print the html file For performance reasons, the number of topics you can print at one time is limited. You are notified if your selection contains too many topics. If the current limit is too restrictive, use the feedback link to suggest a preferable limit. The feedback link is available at the end of most information center pages Under construction! The Information Development Team for IBM WebSphere Application Server is changing its PDF book delivery strategy to respond better to user needs. The intention is to deliver the content to you in PDF format more frequently. During a temporary transition phase, you might experience broken links. During the transition phase, expect the following link behavior: LinkstoWebaddressesbeginningwithhttp://work Links that refer to specific page numbers within the same PdF book work The remaining links will not work. You receive an error message when you click them Thanks for your patience, in the short term, to facilitate the transition to more frequent PDF book updates Copyright IBM Corp. 2008
Changes to serve you more quickly Print sections directly from the information center navigation PDF books are provided as a convenience format for easy printing, reading, and offline use. The information center is the official delivery format for IBM WebSphere Application Server documentation. If you use the PDF books primarily for convenient printing, it is now easier to print various parts of the information center as needed, quickly and directly from the information center navigation tree. To print a section of the information center navigation: 1. Hover your cursor over an entry in the information center navigation until the Open Quick Menu icon is displayed beside the entry. 2. Right-click the icon to display a menu for printing or searching your selected section of the navigation tree. 3. If you select Print this topic and subtopics from the menu, the selected section is launched in a separate browser window as one HTML file. The HTML file includes each of the topics in the section, with a table of contents at the top. 4. Print the HTML file. For performance reasons, the number of topics you can print at one time is limited. You are notified if your selection contains too many topics. If the current limit is too restrictive, use the feedback link to suggest a preferable limit. The feedback link is available at the end of most information center pages. Under construction! The Information Development Team for IBM WebSphere Application Server is changing its PDF book delivery strategy to respond better to user needs. The intention is to deliver the content to you in PDF format more frequently. During a temporary transition phase, you might experience broken links. During the transition phase, expect the following link behavior: v Links to Web addresses beginning with http:// work v Links that refer to specific page numbers within the same PDF book work v The remaining links will not work. You receive an error message when you click them Thanks for your patience, in the short term, to facilitate the transition to more frequent PDF book updates. © Copyright IBM Corp. 2008 xi
xIl Administering applications and their en
xii Administering applications and their environment
Chapter 1 Overview and new features for administering applications and their environments Use the links provided in this topic to learn about the administrative features What is new for administrators This topic provides an overview of new and changed features of system administration Introduction: System administration"on page 17 This topic describes the administration of the product and the applications that run on it. See also"Introduction: Environment"on page 23 and "Introduction: Variables"on page 25 Web applications You create a Web module by assembling servlets, JavaServer Pages(JSP)files, and static content such as Hyper Text Markup Language(HTML) pages into a single deployable unit. You can then deploy the Web module as a stand-alone Web application, or combine it with other modules to create Java Platform, Enterprise Edition(Java EE) applications Whichever application type you deploy, you have the option of activating the Session Manager for your Web module By using this service to manage Http sessions you can personalize Web pages for individual users. A session is a series of requests to a servlet, originating from the same user at the same browser Managing Http sessions allows servlets running in a Web container to keep track of individual For example, a servlet might use sessions to provide"shopping carts"to on-line shoppers. Suppose the servlet is designed to record the items each shopper indicates he or she will purchase from the Web site It is important that the servlet be able to associate incoming requests with particular shoppers. Otherwise the servlet might mistakenly add choices of Shopper 1 to the cart of Shopper 2 EJB applications IBM Web Sphere Application Server provides broad support for enterprise beans, including the Enterprise JavaBeans(EJB)2.x and EJB 3.0 specifications. The EJB 2.x specification includes a container-managed persistence(CMP)2.0 component model, which provides a number of improvements to aid developer productivity and application performance. The EJB 3.0 specification simplifies the development of business logic and data handling for enterprise applications Version support The EJB 3.0 specification simplifies the development of business logic and data handling for enterprise applications. The EJB 2.x specification features a container-managed persistence(CMP)2.0 component model, which provides a number of improvements to aid developer productivity and application In addition, this product continues to fully support enterprise beans written to the CMP 1.1 programming model and deployed in previous versions of this product; applications can use CMP 1.1 beans, CMP 2.0 beans, or a mixture of both CMP 1. 1 beans can be directly carried forward in an EJB 1.1 ejb- jar module or may be repackaged and combined with CMP 2.0 beans in an EJB 2.x module the latest EJB specification and the CMP pers available. a good way to locate some of these is to visit your favorite online bookstore and search on the term Enterprise JavaBeans IBM Corporation 2003, 2005
Chapter 1. Overview and new features for administering applications and their environments Use the links provided in this topic to learn about the administrative features. What is new for administrators This topic provides an overview of new and changed features of system administration. “Introduction: System administration” on page 17 This topic describes the administration of the product and the applications that run on it. See also “Introduction: Environment” on page 23 and “Introduction: Variables” on page 25. Web applications You create a Web module by assembling servlets, JavaServer Pages (JSP) files, and static content such as HyperText Markup Language (HTML) pages into a single deployable unit. You can then deploy the Web module as a stand-alone Web application, or combine it with other modules to create Java™ Platform, Enterprise Edition (Java EE) applications. Whichever application type you deploy, you have the option of activating the Session Manager for your Web module. By using this service to manage HTTP sessions, you can personalize Web pages for individual users. A session is a series of requests to a servlet, originating from the same user at the same browser. Managing HTTP sessions allows servlets running in a Web container to keep track of individual users. For example, a servlet might use sessions to provide ″shopping carts″ to on-line shoppers. Suppose the servlet is designed to record the items each shopper indicates he or she will purchase from the Web site. It is important that the servlet be able to associate incoming requests with particular shoppers. Otherwise, the servlet might mistakenly add choices of Shopper 1 to the cart of Shopper 2. EJB applications IBM WebSphere Application Server provides broad support for enterprise beans, including the Enterprise JavaBeans (EJB) 2.x and EJB 3.0 specifications. The EJB 2.x specification includes a container-managed persistence (CMP) 2.0 component model, which provides a number of improvements to aid developer productivity and application performance. The EJB 3.0 specification simplifies the development of business logic and data handling for enterprise applications. Version support The EJB 3.0 specification simplifies the development of business logic and data handling for enterprise applications. The EJB 2.x specification features a container-managed persistence (CMP) 2.0 component model, which provides a number of improvements to aid developer productivity and application performance. In addition, this product continues to fully support enterprise beans written to the CMP 1.1 programming model and deployed in previous versions of this product; applications can use CMP 1.1 beans, CMP 2.0 beans, or a mixture of both. CMP 1.1 beans can be directly carried forward in an EJB 1.1 ejb-jar module or may be repackaged and combined with CMP 2.0 beans in an EJB 2.x module. Several excellent trade books that cover the latest EJB specification and the CMP persistence model are available. A good way to locate some of these is to visit your favorite online bookstore and search on the term Enterprise JavaBeans. © IBM Corporation 2003, 2005 1
Innovations for EJB 3.0 development The purpose of the EJB 3.0 release is to make things simpler for the developer of enterprise applications In particula the new pe nodel. calle d the jay a pers sistence API( (JPA), is mu mpler than the Container Managed Persistence(CMP)Entity bean approach from earlier releases. With a focus on the premise that a simple Java Bean can be used in most cases, and greater complexity should only be used when called for, EJB 3.0 simplifies the application development process in the following ways Annotations to provide component metadata. It is no longer necessary to create Extensible Markup anguage(XML) deployment descriptors Programmatic defaults so you do not need to specify most commonly used requirements in the EJB container. You only need to specify an item if you do not want the default value a dependency injection function and simpler lookup APls for easier access to a beans environment Plain Old Java Object(POJO) development for both business logic and persistence. This enables unit test outside of the application server, reducing the edit-compile-deploy-debug cycles currently used with pplications. It also removes dependencies on external framework interfaces such as javax. ejb Session Bean, javax. ejb EJBObject, and so on No requirement for session beans to have home interfaces Simplified entity persistence through the JPA Light-weight domain modeling, including inheritance and polymorphism, is supported Refer to Data access resources"on page 7 An overview of data access. Messaging resources" on page 7 An overview of messaging Innovations for EJB 2.x development For EJB 2.x modules, a feature introduced in Version 5 of this product, called Access intent policies, eases the management of interactions between CMP beans and their underlying data stores. Each policy sets data access characteristics such as access type(read or update) and transaction isolation that affect the locking of resources, letting you choose the level of data integrity and performance for your application The Integration Server product adds APls to enable you to further customize IBM-provided access intent policies for your particular environment Access intent is frequently used with the function of application profiling. For example, you can configur one transaction to load an entity bean with strong update locks and configure another transaction to load the same entity bean without locks Sometimes when working with entity beans you might find that it is better to use the dynamic query service rather than the regular EJB query service(which can be referred to as deployment query Your application development can also include asynchronous messaging, which the product supports as a method of communication based on the Java Message Service(JMS)programming interface. The base JMS support enables product applications to exchange messages asynchronously with other JMS clients by using JMS destinations (queues or topics). An application can explicitly poll for messages on a destination. For more information, see Learning about messaging with WebSphere Application Server. The product also provides a message listener service that applications can use to automatically retrieve messages from JMS destinations for processing by message-driven beans, without the application having to explicitly poll JMS destinations Refer to Data access resources"on page 7 An overview of data access Messaging resources"on page 7 An overview of messaging 2 Administering applications and their environment
Innovations for EJB 3.0 development The purpose of the EJB 3.0 release is to make things simpler for the developer of enterprise applications. In particular, the new persistence model, called the Java Persistence API (JPA), is much simpler than the Container Managed Persistence (CMP) Entity bean approach from earlier releases. With a focus on the premise that a simple JavaBean can be used in most cases, and greater complexity should only be used when called for, EJB 3.0 simplifies the application development process in the following ways. v Annotations to provide component metadata. It is no longer necessary to create Extensible Markup Language (XML) deployment descriptors. v Programmatic defaults so you do not need to specify most commonly used requirements in the EJB container. You only need to specify an item if you do not want the default value. v A dependency injection function and simpler lookup APIs for easier access to a bean’s environment. v Plain Old Java Object (POJO) development for both business logic and persistence. This enables unit test outside of the application server, reducing the edit-compile-deploy-debug cycles currently used with applications. It also removes dependencies on external framework interfaces such as javax.ejb.SessionBean, javax.ejb.EJBObject, and so on. v No requirement for session beans to have home interfaces. v Simplified entity persistence through the JPA. Light-weight domain modeling, including inheritance and polymorphism, is supported. Refer to: v “Data access resources” on page 7 An overview of data access. v “Messaging resources” on page 7 An overview of messaging. Innovations for EJB 2.x development For EJB 2.x modules, a feature introduced in Version 5 of this product, called Access intent policies, eases the management of interactions between CMP beans and their underlying data stores. Each policy sets data access characteristics such as access type (read or update) and transaction isolation that affect the locking of resources, letting you choose the level of data integrity and performance for your application. The Integration Server product adds APIs to enable you to further customize IBM-provided access intent policies for your particular environment. Access intent is frequently used with the function of application profiling.For example, you can configure one transaction to load an entity bean with strong update locks and configure another transaction to load the same entity bean without locks. Sometimes when working with entity beans you might find that it is better to use the dynamic query service rather than the regular EJB query service (which can be referred to as deployment query). Your application development can also include asynchronous messaging, which the product supports as a method of communication based on the Java Message Service (JMS) programming interface. The base JMS support enables product applications to exchange messages asynchronously with other JMS clients by using JMS destinations (queues or topics). An application can explicitly poll for messages on a destination. For more information, see Learning about messaging with WebSphere® Application Server. The product also provides a message listener service that applications can use to automatically retrieve messages from JMS destinations for processing by message-driven beans, without the application having to explicitly poll JMS destinations. Refer to: v “Data access resources” on page 7 An overview of data access. v “Messaging resources” on page 7 An overview of messaging. 2 Administering applications and their environment
Client modules Application Clients for WebSphere Application Server follow several programming models with unique requirements and suitability for different types of applications. Most of these models are only available hen you install the product Client modules For a list of supported products and version information, see the Supported Prerequisites Web site Windows ActiveX application client(Windows platforms onl WebSphere Application Server provides an ActiveX to EJB bridge that enables ActiveX programs to access WebSphere Enterprise JavaBeans through a set of ActiveX automation objects Windows Applet client(Windows platforms only) The applet client provides a browser-based Java run time capable of interacting with enterprise beans directly, instead of indirectly through a servlet. J2EE application client The J2EE application client programming model provides the benefits of Java 2 Platform Enterprise Edition(J2EE Windows Pluggable application client( Windows platforms only) The pluggable application client is a thin application client that uses the Sun Java run-time environment (JRE) instead of the IBM JRE environment Thin application client This application client is a Java application client without the J2EE client container support. It uses different programming model than the J2EE application client Related concepts ActiveX application clients WebSphere Application Server provides an ActiveX to EJB bridge that enables ActiveX programs to access enterprise beans through a set of ActiveX automation objects Applet clients The applet client provides a browser-based Java run time capable of interacting with enterprise beans directly, instead of indirectly through a servlet Java EE application clients The Java Platform, Enterprise Edition (Java EE) application client programming model provides the benefits of the Java EE Platform for Web Sphere Application Server Enterprise product Pluggable application clients The Pluggable application client provides a lightweight, downloadable Java application run time capable of interacting with enterprise beans Thin application clients The Thin application client provides a lightweight, downloadable Java application run time capable of interacting with enterprise beans Web services Web services are a technology that invoke services or applications using Internet standards and protocols mplementing a service-oriented architecture, you can use Web services to perform encapsulated business functions ranging from simple request-reply to full business process interactions. Web services are self-contained, modular applications that you can describe, publish, locate, and invoke over a network WebSphere Application Server implements a number of core technologies on which Web services are developed and implemented Chapter 1 Overview and new features: Administering 3
Client modules Application Clients for WebSphere Application Server follow several programming models with unique requirements and suitability for different types of applications. Most of these models are only available when you install the product. Client modules For a list of supported products and version information, see the Supported Prerequisites Web site. Windows ActiveX application client (Windows® platforms only) WebSphere Application Server provides an ActiveX to EJB bridge that enables ActiveX programs to access WebSphere Enterprise JavaBeans™ through a set of ActiveX automation objects. Windows Applet client (Windows platforms only) The applet client provides a browser-based Java run time capable of interacting with enterprise beans directly, instead of indirectly through a servlet. J2EE application client The J2EE application client programming model provides the benefits of Java 2 Platform, Enterprise Edition (J2EE). Windows Pluggable application client (Windows platforms only) The pluggable application client is a thin application client that uses the Sun Java run-time environment (JRE) instead of the IBM® JRE environment. Thin application client This application client is a Java application client without the J2EE client container support. It uses a different programming model than the J2EE application client. Related concepts ActiveX application clients WebSphere Application Server provides an ActiveX to EJB bridge that enables ActiveX programs to access enterprise beans through a set of ActiveX automation objects. Applet clients The applet client provides a browser-based Java run time capable of interacting with enterprise beans directly, instead of indirectly through a servlet. Java EE application clients The Java Platform, Enterprise Edition (Java EE) application client programming model provides the benefits of the Java EE Platform for WebSphere Application Server Enterprise product. Pluggable application clients The Pluggable application client provides a lightweight, downloadable Java application run time capable of interacting with enterprise beans. Thin application clients The Thin application client provides a lightweight, downloadable Java application run time capable of interacting with enterprise beans. Web services Web services are a technology that invoke services or applications using Internet standards and protocols. Implementing a service-oriented architecture, you can use Web services to perform encapsulated business functions ranging from simple request-reply to full business process interactions. Web services are self-contained, modular applications that you can describe, publish, locate, and invoke over a network. WebSphere Application Server implements a number of core technologies on which Web services are developed and implemented. Chapter 1. Overview and new features: Administering 3