Local Clients

A local client has these characteristics:

• It must run in the same application as the enterprise bean it accesses.

• It can be a web component or another enterprise bean.

• To the local client, the location of the enterprise bean it accesses is not transparent.

The no-interface view of an enterprise bean is a local view. The public methods of the enterprise bean implementation class are exposed to local clients that access the no-interface view of the enterprise bean. Enterprise beans that use the no-interface view do not implement a business interface.

The local business interface defines the bean’s business and lifecycle methods. If the bean’s business interface is not decorated with @Local or @Remote, and the bean class does not specify the interface using @Local or @Remote, the business interface is by default a local interface.

To build an enterprise bean that allows only local access, you may, but are not required to do one of the following:

• Create an enterprise bean implementation class that does not implement a business interface, indicating that the bean exposes a no-interface view to clients. For example:

  @Session
  public class MyBean { ... }

• Annotate the business interface of the enterprise bean as a @Local interface. For example:

  @Local
  public interface InterfaceName { ... }

• Specify the interface by decorating the bean class with @Local and specify the interface name. For example:

  @Local(InterfaceName.class)
  public class BeanName implements InterfaceName { ... }

Accessing Local Enterprise Beans Using the No-Interface View

Client access to an enterprise bean that exposes a local, no-interface view is accomplished either through dependency injection or JNDI lookup.

Clients do not use the new operator to obtain a new instance of an enterprise bean that uses a no-interface view.

Example 14–2 Injecting an Enterprise Bean Using the No-Interface View

To obtain a reference to the no-interface view of an enterprise bean through dependency injection, use the javax.ejb.EJB annotation and specify the enterprise bean's implementation class.

@EJB
ExampleBean exampleBean;

Example 14–3 Looking Up an Enterprise Bean Using the No-Interface View

To obtain a reference to the no-interface view of an enterprise bean using JNDI lookup, use the javax.naming.InitialContext interface's lookup method.

ExampleBean exampleBean = (ExampleBean) 
        InitialContext.lookup("java:module/ExampleBean");

Accessing Local Enterprise Beans That Implement Business Interfaces

Client access to enterprise beans that implement local business interfaces is accomplished using either dependency injection or JNDI lookup.

Example 14–4 Injecting an Enterprise Bean's Local Business Interface

To obtain a reference to the local business interface of an enterprise bean through dependency injection, use the javax.ejb.EJB annotation and specify the enterprise bean's local business interface name.

@EJB
Example example;

Example 14–5 Looking Up a Local Enterprise Bean Using JNDI

The obtain a reference to a local business interface of an enterprise bean using JNDI lookup, use the javax.naming.InitialContext interface's lookup method.

ExampleLocal example = (ExampleLocal)
         InitialContext.lookup("java:module/ExampleLocal");