instance.properties Binaries Cluster Node Settings Instance Host1 DB R Cluster_data Binaries Global settings Instances Host 1
Settings cluster node 1 Settings cluster node n
Host n Server/ Dispatcher Process R Config Manager BootStrap Offline ConfigurationManager Cluster Configuration Tool Cluster Admin R Bootstrap Binaries Bootstrap Settings JControl Installed by SAPInst
Shell Console Commands Servers Configuration Configuration Manager
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J2EE Deployment 1/4
Development Assembly Deployment
IDE Archive (.jar) Archive (.jar) EJB components (Enterprise Bean) Archive (.ear) Bean developer Application
Assembler Deployer J2EE Server Service Server Provider Container Provider System administrator Deployment tools Admin- Tools Archive (.war) Web components (e.g. Servlet, JSP etc.)
Web Container
EJB Container
Separation of Tasks (Role Concept)
Bean Bean developers develop Enterprise Beans that implement the business logic for a developer specific specialist area as reusable SW components. Bean developers forward their
components as jar-archive files, which contain meta data in an XML file
(deployment descriptor) in addition to the compiled classes and interfaces. Component features and their requirements of the (as yet unknown) runtime environment are
contained in a declarative format.
Application Application assemblers use the components provided for a specific application by assembler combining several components as larger conglomerates. They have the option of adding
additional Java beans here. The overall archive created here is also known as a Deployment Unit or EJB Module.
Deployer Deployers are experts for a specific system environment and are familiar with the server and container products used. They use deployment tools to integrate the deployment unit in the server.
Container Container providers provide the specialist tools for the respective container and server. Provider
System The system administrator is responsible for the infrastructure required to operate the Admin server, configures and binds the system services and resources required and uses tools
©SAP AG 2004, Web AS Java Installation and Upgrade
J2EE Deployment 2/4
Assembly IDE Archive (.jar) Archive (.jar) Bean developer Archive (.war) Deployment DevelopmentEnterprise Java Beans contain business logic or represent data from a database.
Separation of Business Logic and Platform
J2EE defines strict encapsulation of business logic as components (Enterprise Java Beans, EJBs). These components are installed to be run on a specific platform (Web Container for a J2EE Server). EJBs communicate with the container for the application server via
standard interfaces and are therefore platform-independent. Enterprise Java Beans
EJBs are the smallest components within the EJB architecture. This means that they can only be forwarded or exchanged as a total unit. An additional significant characteristic here is the fact that bean developers can focus on implementing business logic. Runtime logic (such as transaction control) has been implemented in the EJB Container. The bean developer uses the corresponding entries in the deployment descriptors to determine whether they can use the runtime logic for the container. Bean developers can also implement the runtime logic themselves.
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Assembly
IDE
Archive (.jar)
Archive (.jar) Archive (.ear) Bean developer Application
Assembler
Archive (.war)
web.xml ejb-jar.xml application.xml
Deployment Development
Runtime logic such as transaction control or security checks is requested
via entries in deployment descriptors.
Each archive contains a deployment descriptor (XML format).
J2EE Deployment 1/4
WAR/JAR/EAR: Declarative Specification by Deployment Descriptors
A series of formats in which the compiled form of J2EE applications (class-files, JSP, HTML files, pictures etc) are packed, have been defined for J2EE so that these can be installed on an application server for execution.
EJB-JAR All (auxiliary) classes and interfaces for EJB are saved here with a standardized XML deployment descriptor (ejb-jar.xml).
The deployment descriptor describes the EJBs and their contexts and features, such as the JNDI name, transaction features etc.
WAR W(eb)AR(chive) files contain the "web section" of J2EE applications, such as servlets, JSPs, HTML files, pictures etc. A corresponding Web Archive Deployment Descriptor is also available here.
EAR JAR and WAR files are bundled ("assembly") as a J2EE total application in J2EE E(nterprise) AR(chive) files.
©SAP AG 2004, Web AS Java Installation and Upgrade EAR file Deployer Deployment tools Deployment Web Container EJB Container EJB Verifier Container Compiler Remote Compiler Remote Object 1 . . .
2 public String doSomething() {
3 // authentificate user 4 // start transaction 5 String s = bean.doSomething(); 6 // stop transaction 7 return s; 8 } 9 . . .
Deployment descriptors contain information on how components are installed on the respective application server (declarative specification).
Entries in the DD are used to generate additional classes
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DeploymentThis work step has not been standardized in the J2EE Specification. Each container product has its own solution here.
During deployment of an EJB Jar file, the following steps are usually executed by the container:
The system checks whether components in the EJB Jar file adhere to the rules in the EJB specification.
The container tool generates the EJB and home classes for the Enterprise Beans. Methods in the remote object correspond to methods in the Enterprise Bean.
However, methods in the remote object contain additional code that is added using entries in the deployment descriptor. The remote object then acts as a proxy object.
Line 2: The generated class provides the same method as the actual bean.
Line 3: Implementation of the runtime logic takes place within the remote class. The deployment tool inserts additional code here, e.g for transaction control etc. Line 5: Actual calls of the bean method take place here..
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You should now be able to:
z Start/Stop the Visual Admin, Config Tool, SDM, Shell console and Configuration Editor
z Change the configuration of the J2EE server using the Visual Admin. Config Tool, and Shell Console. z Offline configuration of the J2EE Engine with the
Configuration Editor
z Mange the J2EE Engine Repository with the SDM z Do (Un-)Deployments with the SDM