The answers listed here which guide you to use SOAPHandler are fully correct. The benefit of that approach is that it will work with any JAX-WS implementation, as SOAPHandler is part of the JAX-WS specification. However, the problem with SOAPHandler is that it implicitly attempts to represent the whole XML message in memory. This can lead to huge memory usage. Various implementations of JAX-WS have added their own workarounds for this. If you work with large requests or large responses, then you need to look into one of the proprietary approaches.
Since you ask about "the one included in JDK 1.5 or better" I'll answer with respect to what is formally known as JAX-WS RI (aka Metro) which is what is included with the JDK.
JAX-WS RI has a specific solution for this which is very efficient in terms of memory usage.
See https://javaee.github.io/metro/doc/user-guide/ch02.html#efficient-handlers-in-jax-ws-ri. Unfortunately that link is now broken but you can find it on WayBack Machine. I'll give the highlights below:
The Metro folks back in 2007 introduced an additional handler type, MessageHandler<MessageHandlerContext>, which is proprietary to Metro. It is far more efficient than SOAPHandler<SOAPMessageContext> as it doesn't try to do in-memory DOM representation.
Here's the crucial text from the original blog article:
MessageHandler:
Utilizing the extensible Handler framework provided by JAX-WS
Specification and the better Message abstraction in RI, we introduced
a new handler called MessageHandler to extend your Web Service
applications. MessageHandler is similar to SOAPHandler, except that
implementations of it gets access to MessageHandlerContext (an
extension of MessageContext). Through MessageHandlerContext one can
access the Message and process it using the Message API. As I put in
the title of the blog, this handler lets you work on Message, which
provides efficient ways to access/process the message not just a DOM
based message. The programming model of the handlers is same and the
Message handlers can be mixed with standard Logical and SOAP handlers.
I have added a sample in JAX-WS RI 2.1.3 showing the use of
MessageHandler to log messages and here is a snippet from the sample:
public class LoggingHandler implements MessageHandler<MessageHandlerContext> {
public boolean handleMessage(MessageHandlerContext mhc) {
Message m = mhc.getMessage().copy();
XMLStreamWriter writer = XMLStreamWriterFactory.create(System.out);
try {
m.writeTo(writer);
} catch (XMLStreamException e) {
e.printStackTrace();
return false;
}
return true;
}
public boolean handleFault(MessageHandlerContext mhc) {
.....
return true;
}
public void close(MessageContext messageContext) { }
public Set getHeaders() {
return null;
}
}
(end quote from 2007 blog post)
Needless to say your custom Handler, LoggingHandler in the example, needs to be added to your Handler Chain to have any effect. This is the same as adding any other Handler, so you can look in the other answers on this page for how to do that.
You can find a full example in the Metro GitHub repo.
