EJB applications
This page provides a starting point for finding information about enterprise beans.
Based on the EJB specification, enterprise beans are Java components that typically implement the business logic of J2EE applications as well as access data.
Subtopics
- Enterprise beans
An enterprise bean is a Java component that can be combined with other resources to create Java applications. There are three types of enterprise beans, entity beans, session beans, and message-driven beans.
- Java EE application resource declarations
We can configure the Java Enterprise Edition (Java EE) applications to declare dependencies on external resources and configuration parameters. These resources might be injected into the application code, or might be accessed by the application through the JNDI.
- Message-driven beans - automatic message retrieval
WebSphere Application Server supports the use of message-driven beans as asynchronous message consumers.
- Access intent policies for EJB 2.x entity beans
An access intent policy is a named set of properties or access intents that govern data access for EJB persistence. We can assign policies to an entity bean and to individual methods on an entity bean's home, remote, or local interfaces during assembly. We can set access intents only within EJB Version 2.x-compliant and later modules for entity beans with CMP Version 2.x.
- Java Persistence API (JPA) architecture
Data persistence is the ability to maintain data between application executions. Persistence is vital to enterprise applications because of the required access to relational databases. Applications developed for this environment must manage persistence themselves or use third-party solutions to handle database updates and retrievals with persistence. The Java Persistence API (JPA) provides a mechanism for managing persistence and object-relational mapping and functions for the EJB 3.0 and EJB 3.1 specifications.
- Transaction support in WebSphere Application Server
Support for transactions is provided by the transaction service within WebSphere Application Server. The way that applications use transactions depends on the type of application component.
Related information:
End-to-end paths for EJB applications
Troubleshooting EJB applications