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If the message objects returned from the back end have the following TYPE, MESSAGE, ID, NUMBER, MESSAGE_V1, MESSAGE_V2, MESSAGE_V3 and MESSAGE_V4 fields, then setting messageKeys is all the configuration you need to do (these are automatically dealt with). However, if some other type of object is returned instead that doesn't have these fields, you will need to add code in the convertRFCMessage method in your service implementation to convert these message objects to the RFCMessage type.
See section Spring config for Actions for information on how to override messages returned from RFC.
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