processing attachments in web service

[Tom Griffith]

Hello. if anybody has a minute, I can't seem to get a grasp on this. I have a web service that accepts parameters and returns a response string, no problem. I modified the client to send an attachment. however, I can't figure out how to make the web service implementation class process attachments. It seems to begin with having to obtain a handle to the incomng SOAPMessage, right...via SOAPMessageContext and MessageContext? Therein lies my problem (if what i said is true)...i can't figure out how to obtain or instantiate the/a MessageContext inside the web service...

something along the lines of...

MessageContext context = MessageContext.getCurrentContext();

does anybody have an example that begins before a MessageCntext object is created? Again, i just don't know how to instantiate a MessageContext inside the web service (if that is indeed the approach). Is it similar to servlets on some level where I need to obtain the request object?

Thank you very much for reading and for your time.

[Peer Reynders]

You didn't mention which technology you are using.

JAX-RPC :
In a SOAP Message handler it is handed to you:

javax.xml.rpc.handler.Handler.handleRequest(javax.xml.rpc.handler.MessageContext context);
javax.xml.rpc.handler.Handler.handleResponse(javax.xml.rpc.handler.MessageContext context);


In a JAX-RPC Servlet endpoint (JSE) you get it through ServiceEndpointContext.getMessageContext()

public class MyJseServiceImpl extends MyService {
    ServletEndpointContext context;
    ...
    public void init(Object context) throws ServiceException {
        try {
            this.context = (ServletEndpointContext) context;
            ...
    }
 
    public String getResult(String input) {
        SOAPMessageContext messageContext = (SOAPMessageContext) context.getMessageContext()
        ...
    }
    ...
}

In an EJB endpoint you get it through SessionContext.getMessageContext().

import javax.ejb.SessionContext;
import javax.xml.rpc.handler.soap.SOAPMessageContext;
 
public class MyServiceBean implements javax.ejb.SessionBean {
    SessionContext context;
    ...
    public void setSessionContext(SessionContext context) {
        this.context = context;
    }
    ...
    public String getResult(String input) {
        SOAPMessageContext messageContext = (SOAPMessageContext) context.getMessageContext()
        ...
    }
    ...    
}

That being said attachments in JAX-RPC are usually being handled with javax.activation.DataHandler.

SOAP attachments with JAX-RPC

This makes some sense as "SOAP with Attachments" are actually sent in a multi-part MIME envelope (the SOAP envelope travels in the first part) and DataHandlers were designed to deal with the serialization/de-serialization of MIME types.



JAX-WS 2.0:
You get the MessageContext through WebServiceContext.getMessageContext()

@Resource 
WebServiceContext wsContext;
 
@WebMethod
public String getResult(String input) {
    MessageContext context = wsContext.getMessageContext();
    .......
}

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