2-6 Deploying Applications to Oracle WebLogic Server
modules JARs depending on the implementation; typically the WAR or EJB JAR file is then packaged in an Enterprise application. See Getting Started With JAX-WS Web
Services for Oracle WebLogic Server.
2.4.6 J2EE Library
A J2EE library is a standalone J2EE module, or multiple J2EE modules packaged in an Enterprise application EAR, that is registered with the J2EE application container as a
shared library at deployment time. After a J2EE library has been registered, you can deploy Enterprise applications that reference the library in their
weblogic-application.xml deployment descriptors. Each referencing application receives a copy of the shared J2EE library modules on deployment, and can use those
modules as if they were packaged as part of the application itself. J2EE library support provides an easy way to share one or more J2EE modules among multiple Enterprise
applications without physically adding the shared modules to each dependent application.
The deployment files of a shared library resemble either a standard Enterprise application or J2EE module, as discussed in this section. Shared libraries differ from
standard EARs and modules only by the contents of their MANIFEST.MF files. Creating Shared J2EE Libraries and Optional Packages in Developing Applications for
Oracle WebLogic Server describes how to assemble and configure J2EE libraries, and how to configure Enterprise applications that utilize J2EE libraries.
Section 6.11, Deploying Shared Java EE Libraries and Dependent Applications describes how to deploy J2EE libraries and Enterprise applications that reference J2EE
libraries.
2.4.7 Optional Package
Optional packages provide similar functionality to J2EE libraries, allowing you to easily share a single JAR file among multiple applications. However, optional
packages function as individual J2EE modules standalone or within an Enterprise application, rather than as an Enterprise application. For example, third-party Web
Application Framework classes needed by multiple Web applications can be packaged and deployed in a single JAR file, and referenced by multiple Web application
modules in the domain.
Optional packages are delivered as basic JAR files that have no deployment descriptors. You simply designate the JAR as an optional package at deployment time,
and WebLogic Server registers the file with the target servers you select. After the optional package has been registered, you can then deploy J2EE modules and
applications that reference the optional package in their MANIFEST.MF files. Creating Shared J2EE Libraries and Optional Packages in Developing Applications for Oracle
WebLogic Server describes how to assemble and configure optional packages, and how to configure J2EE modules that utilize optional packages.
Section 6.11, Deploying Shared Java EE Libraries and Dependent Applications describes how to deploy optional packages and J2EE modules that reference optional
packages.
2.4.8 JDBC, JMS, and WLDF Modules
A JMS, JDBC, or WebLogic Diagnostic Framework WLDF application module can be deployed as a standalone resource, in which case the resource is available in the
domain targeted during deployment, or as part of an Enterprise application. An application module deployed as part of an Enterprise application is available only to
Understanding WebLogic Server Deployment 2-7
the enclosing application an application-scoped resource. Using application-scoped resources ensures that an application always has access to required resources, and
simplifies the process of deploying the application into new environments.
In contrast to system modules, application modules are owned by the developer who created and packaged the module, rather than the Administrator who deploys the
module. This means that the Administrator has more limited control over JDBC, JMS, and WLDF application modules. When deploying an application module, an
Administrator can change resource properties that were specified in the module, but cannot add or delete resources.
System modules are created by the Administrator via the WebLogic Administration Console, and can be changed or deleted as necessary by the Administrator. Similarly,
standalone application modules created by the Administrator can be used to recreate global resources in multiple WebLogic Server environments simply by deploying the
modules into new domains.
For more information on how to deploy and use JDBC, JMS, and WLDF modules, see:
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Section 6.8, Deploying JDBC, JMS, and WLDF Application Modules
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Configuring and Managing JMS for Oracle WebLogic Server
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Configuring and Managing JDBC for Oracle WebLogic Server
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Configuring and Using the Diagnostics Framework for Oracle WebLogic Server
2.4.9 Client Application Archive
The J2EE specification enables you to include a client application archive file within an Enterprise application. A J2EE client application module contains the Java classes that
execute in the client JVM Java Virtual Machine and deployment descriptors that describe EJBs Enterprise JavaBeans and other WebLogic Server resources used by the
client. This enables both the server-side and client-side components to be distributed as a single unit. You define client modules in an EAR using the J2EE standard
application-client.xml deployment descriptor and WebLogic Server weblogic-appclient.xml descriptor.
2.5 Deployment Tools
