Apache CXF - share data between In and Out interceptors

You can store values on the Exchange. CXF creates an Exchange object for each request to act as a container for the in and out messages for the request/response pair and makes it accessible as message.getExchange() from both.

In interceptor:

public void handleMessage(Message inMessage) throws Fault {
  inMessage.getExchange().put("com.example.myKey", myCustomObject);
}

Out interceptor

public void handleMessage(Message outMessage) throws Fault {
  MyCustomObject obj = (MyCustomObject)outMessage.getExchange().get("com.example.myKey");
}

(or vice-versa for client-side interceptors, where the out would store values and the in would retrieve them). Choose a key that you know won't be used by other interceptors - a package-qualified name is a good choice. Note that, like Message, Exchange is a StringMap and has generic put/get methods taking a Class as the key that give you compile-time type safety and save you having to cast:

theExchange.put(MyCustomObject.class, new MyCustomObject());
MyCustomObject myObj = theExchange.get(MyCustomObject.class);

Your interceptors have access to javax.xml.ws.handler.MessageContext. This extends Map<String,Object>, so you can put whatever you want into the context and access it later on in the request:

public boolean handleMessage(final MessageContext context) {
    context.put("my-key", myCustomObject);
            // do whatever else your interceptor does
}

Later on:

public boolean handleMessage(final MessageContext context) {
    MyCustomObject myCustomObject = context.get("my-key");
            // do whatever else your interceptor does
}