Service Data Objects (SDO) is an open standard for enabling applications to handle data from different data sources in a uniform way (as DataGraphs). The service integration bus Web services enablement uses an SDO repository (database) for storing and serving WSDL definitions.
JAX-RPC handlers are invoked by the IBM Web services run-time environment during processing of request and response messages. For messages that are exchanged using the SOAP protocol, each JAX-RPC handler is passed a SOAP-specific MessageContext object. For other protocols, the IBM Web services run-time environment passes a MessageContext object that provides an SDO view of the message.
If the JAX-RPC handler only deals with message context properties, then it does not need to be aware of the particular subclass of MessageContext that it is given, because the context property methods are defined by the MessageContext interface itself. If the handler needs to process information contained within the message, then it must be coded to work with the required subclasses. It is recommended that your JAX-RPC handlers test whether the MessageContext is an instance of the required subclass.
The SDOMessageContext class provides methods to get and set the com.ibm.websphere.sdo.SDOMessage instance that represents the actual message being processed. The SDOMessage in turn has a method to access the SDO DataGraph object that holds the message content as SDO DataObjects.
A JAX-RPC handler can modify the SDO DataGraph contents, but it cannot change the format or schema of the message.
Here is an example of the code that is used to access the SDO DataGraph from the MessageContext object in a JAX-RPC handler handleRequest method:
public boolean handleRequest(MessageContext messageContext) { // Convert the MessageContext into an SDOMessageContext if( messageContext instanceof SDOMessageContext) { SDOMessageContext smc = (SDOMessageContext)messageContext; // Retreive the message SDOMessage message = smc.getSDOMessage(); // Get the root object in the SDO DataGraph DataGraph graph = message.getDataGraph(); DataObject content = graph.getRootObject(); // Now do something with the message content..... } return true; }