Web application components

The Web Application Pattern contains components that represent middleware services that are required by the virtual application instance.

You can connect components in a virtual application pattern to indicate dependencies and optionally apply a policy to configure middleware services during deployment to configure specific behavior or define a quality of service level. Components, links, and policies can have required and optional attributes.

Components, links, and policies are defined by plug-ins. When you create a virtual application pattern, the available components, links, policies, and configuration options are determined by the plug-ins that are included with the selected pattern type.

Components

The following components are available with the Web Application Pattern.
  • Application
    • Additional archive file (web application)
    • Additional archive file (Java application)
    • Enterprise application component
    • Existing Web Service Provider Endpoint
    • Java application (IBM Java Runtime Version 7) (Java application)
    • Policy Set
    • Web application component
  • Database
    • Database Studio web console
    • Database (DB2®), such as IBM® DB2
    • Existing database (DB2)
    • Existing database (Informix®)
    • Existing database (Oracle)
    • Existing IMS™ database
  • Messaging
    • Existing Messaging Service (WebSphere® MQ)
    • Topic
    • Queue
  • OSGi
    • Existing OSGi Bundle Repository (WebSphere Application Server)
    • OSGi Application (WebSphere Application Server)
  • Transaction Processing
    • Existing CICS® Transaction Manager
    • Existing IMS Transaction Manager
  • User Registry
    • Existing User Registry (IBM Tivoli® Directory Server)
    • Existing User Registry (Microsoft Active Directory)
    • User Registry (Tivoli Directory Server)
  • Other components
    • Connect Out
    • Connect In
    • "Connect in" (deprecated) (Java application)
    • "Connect out" (deprecated) (Java application)
    • Monitored file (Java application)
    • HTTP Listener (Java application)

Policies

You can optionally apply policies to a virtual application to configure specific behavior in the deployed virtual application instance. Two virtual applications might include identical components, but require different policies to achieve different service level agreements. For example, if you want a web application to be highly available, you can add a scaling policy to the web application component and specify requirements such as a processor usage threshold to trigger scaling of the web application. At deployment time, the topology of the virtual application is configured to dynamically scale the web application. Multiple WebSphere Application Server instances are deployed initially for the web application and instances are added and removed automatically based on the service levels that are defined in the policy.

Policies can be applied only to particular types of components. For more information, see the following links:
  • Scaling policy
  • Routing policy
  • Log policy
  • JVM policy (web application)
  • JVM policy (Java application)
  • Interim fix policy
  • Routing Policy (Java application)
  • Scaling Policy (Java application)