Introduction

Coherence integrates closely with Oracle WebLogic Portal^TM . Specifically, Coherence includes the following integration points:

1. Coherence*Web for HTTP session state management
2. P13N CacheProvider SPI implementation
3. A blueprint for efficiently sharing data between WSRP-federated portals that leverages Coherence and the WebLogic Portal Custom Data Transfer mechanism

Coherence*Web Support

Coherence*Web can be installed in a WebLogic Portal environment to provide session state management in based on Coherence. Coherence*Web allows for more advanced Deployment Models, Coherence*Web Session Models and Coherence*Web Locking Modes in a clustered environment.

P13N CacheProvider SPI Implementation

Internally, WebLogic Portal uses its own caching service to cache portal, personalization, and commerce data as described here:

http://download.oracle.com/docs/cd/E13155_01/wlp/docs103/javadoc/com/bea/p13n/cache/package-summary.html

WebLogic Portal 8.1.6 and later includes an SPI for the P13N caching service that can be implemented by third party cache vendors. Coherence includes a P13N CacheProvider SPI implementation that - when installed into a WebLogic Portal application - will transparently manage cached P13N data without requiring code changes. Additionally, combining Coherence and WebLogic Portal gives you extreme flexibility in your choice of cache topologies. For example, if you find that your Portal servers are bumping into the 4GB heap limit (on 32-bit JVMs) or are experiencing slow GC times, you can leverage a cache client/server topology to move serializable P13N state out of your Portal JVMs and into one or more dedicated Coherence cache servers, thus reducing your Portal JVM heap size and GC times. Also, you can leverage the Coherence Management Framework to closely monitor statistics to better tune your P13N cache settings. Finally, the Coherence CacheProvider also allows your portlets to leverage Coherence caching service by using the standard P13N Cache API.

To install the Coherence P13N CacheProvider, simply:

1. Copy the coherence-wlp.jar and coherence.jar libraries included from the lib directory of the Coherence installation to the APP-INF/lib directory of your WebLogic Portal application.
2. Configure the Coherence P13N CacheProvider as the default provider in the p13n-cache-config.xml file found in each of your WLP application's META-INF directory. Specifically, add:
   
   

   <default-provider-id>com.tangosol.coherence.weblogic</default-provider-id>

   
   immediately before the first <cache> element.

Please see the JavaDoc for the PortalCacheProvider class for details on configuring the Coherence CacheProvider and Coherence caches used by the provider. Additionally, please see the following document for a list of some of the caches used by WebLogic Portal:

http://download.oracle.com/docs/cd/E13155_01/wlp/docs103/caches/caches.html

Sharing Data Between WSRP-Federated Portals Using Coherence

The Web Services for Remote Portlets (WSRP) protocol was designed to support the federation of portals hosted by arbitrary portal servers and server clusters. Developers use WSRP to aggregate content and the user interface (UI) from various portlets hosted by other remote portals. By itself, though, WSRP does not address the challenge of implementing scalable, reliable, and high-performance federated portals that create, access, and manage the lifecycle of data shared by distributed portlets. Fortunately, WebLogic Portal provides an extension to the WSRP specification that — when coupled with Oracle Coherence — allows WSRP Consumers and Producers to create, view, modify, and control concurrent access to shared, scoped data in a scalable, reliable, and highly performant manner.

See the following document for complete details:

http://www.oracle.com/technology/pub/articles/dev2arch/2005/11/federated-portal-cache.html