Chapter 8 Creating Enterprise JavaBeans Clients

Calling local interface methods

You can use EJB local invocations in servlet, JSP, or EJB component code to call EJB components hosted on the same server. Proxies for a local bean can be instantiated with almost the same code that would be used to instantiate remote proxies. The differences are:

You must create a local EJB reference for the called EJB component, and use the aliased JNDI name defined in the EJB local reference.
Parameters that are not primitive types are passed by reference, not by value. Changes to a parameter in the component implementation affect the variable passed from the caller.
You must narrow to the local home interface type, not the home interface type.
Local interfaces are available only to EJB components, Java servlets, and JSPs hosted on the same server as the target component. You must configure a local EJB reference for the call, as described in "Adding an EJB local reference" and "Editing an EJB local reference".
If local interfaces are used, both the caller and the called component must be loaded by the same custom class loader. See "For calls to EJB components with local interfaces" for more information.