Federated transactions have special federated proxies that convert the federated transaction names (such as getPartyFederated) to actual transaction names (such as getParty) and then send the transactions to the Federator module.
The Federator module retrieves federated profile or instance metadata, checks user access rights, and sends transaction requests to the appropriate federated instance.
The Federated Deployment framework provides the RMIProtocolAdapter class to enable RMI communication between instances. In order to support other communication protocols, new protocol adapters can be written and configured in Federated Deployment metadata.
All protocol adapters must implement the ProtocolAdapter interface. The sendRequest() method takes DWLTransaction as the input parameter and returns DWLFederatedInstanceResultBObj. RMIProtocolAdapter sends transaction requests to remote instances using the standard MDM request XML format (parser=TCRMService). The response is returned from remote instance in the same format that you specify in the Constructor context property in the federated transaction request. RMIProtocolAdapter uses XMLFederatedResponseConstructorHelper to extract the response object from the remote transaction response and places it in the finalResponse field of the DWLCommon object returned as part of DWLFederatedInstanceResultBObj. The standard response constructor, XMLResponseConstructor, retrieves the formatted response message from the finalResponse field and adds it to the federated transaction response message unmodified.
InfoSphere® MDM supports both RMI and web services invocations for federated transactions. However, invocation between the local and remote instances is always RMI regardless of the type of incoming invocation on the local instance. For web services invocation, the constructor FederatedWSResponseConstructor converts the RMI formatted response from the remote instances to web services formatted response. This is the final federated transaction response.