WebLogic: The Definitive Guide

SOAP Message Handlers

As depicted earlier in Figure 19-2, you may associate a chain of SOAP message handlers with a web service operation. SOAP message handlers are a part of the JAX-RPC standard. A SOAP message handler can be tied to a web service endpoint either on the client side or on the server side. It is used simply to provide additional logic for handling the SOAP messages. Each SOAP handler in the chain intercepts the request and response SOAP messages, and processes the SOAP message before passing it on to the next member in the chain. Each message handler has access to the SOAP message and can transform the incoming request or outgoing response before passing it on to the next SOAP handler. For this reason, SOAP handlers are best suited to implement a number of useful add-on features such as logging, encryption and decryption, and caching.

The rest of this section describes how to write and deploy SOAP message handlers, and how to associate a chain of SOAP handlers with operations of WebLogic web services. If you need to create message handlers that process SOAP messages on the client side, you should refer to the JAX-RPC specification for more information.

Life Cycle of a SOAP Handler

Every SOAP handler implements the javax.xml.rpc.handler.Handler interface. Example 19-13 describes the methods exposed by the Handler interface.

Example 19-13. The javax.xml.rpc.handler.Handler interface

package javax.xml.rpc.handler; public interface Handler { public boolean handleRequest(MessageContext ...