Message transformers are implementations of the Enterprise Integration Pattern (EIP) named Message Translator, which deal with parity between data formats across endpoints. It's a neat design to decouple message producers and message consumers—none of them are required to know the format expected by the other. It is almost like the adapter pattern from the core java design principle, which acts as an enabler across producers and consumers. Let's take a more generic example, we regularly transfer files across Windows and Linux even though the format required on these two systems is different, the underlying application takes care of transforming from one format to another.

Spring Integration provides a lot of out-of-the-box transformers without taking away flexibility to define and extend new transformers. It has provided extensive support for the most commonly used message exchange formats such as XML, JSON, Collections, and others. Out of these, by and large...