Program guide > (deprecated) Partitioning facility > Partitioning facility programming > Partitioned EJB overview


Deprecated feature: The partitioning facility (WPF) feature is deprecated. You can configure partitioning with WebSphere eXtreme Scale.


Interface for a partitioned stateless session bean

A partitioned stateless session bean (PSSB) and PRSB can directly provide an interface for remote method invocations to a remote server infrastructure (or locally, as well, if within the same server side JVM). However, often programmers would like to have a single façade to these sorts of partitioning facility (WPF) framework bean types, and the server implementation would execute the PSSB and PRSB bean functionality. This is not only for Enterprise JavaBeans™ (EJB) programmers, but also for those implementing servlets for example.

To implement this, a simple example, the WPFFacadePartitionSample, is provided.

This sample caches the remote home of an example PSSB bean and provides a single, non-routable method implementation that executes the PSSB method on the server JVM. The source code is included in the WPFFacadePartitionSample.ear.

This approach does have an advantage. If the client uses only a façade interface, and the PSSB/PRSB client routing portion is executed in the server infrastructure, the general routing functionality will be faster as the client routing state information does not have to be downloaded and cached in the client JVM making the request. For example, the WPFKeyBasedPartitionSample.ear sample client (WPFKeyBasedPartitionClient.java) uses JNDI and directly instantiates the PSSB home instance and creates an instance from it. Each remote method invocation on the instance requires the client JVM to acquire routing information, download the client JVM, and then cache it. The download step can add overhead to the client implementation in terms of performance (the routing data is cached and stored in memory for both cases so there is not a memory footprint savings). For the case where a user solution has thousands of partitions and many clients in separate client JVMs, bottlenecks can arise when transferring this much information and, if possible, is best to avoid.

Both façade and non-façade approaches are supported and useful in certain scenarios.


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Partitioned EJB overview


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Partitioned EJB overview


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