Spring Integration REST service consuming both XML and JSON - spring-integration

Question

I would like to implement the following simple use case with Spring Integration v4.2+:
A REST endpoint is provided to clients, for example (/api/person).
The clients can POST data to this endpoint. The data can be submitted in JSON, XML or Google Protocol Buffers format.
The application accepts the data and saves it to a database table.
I have the following Spring Integration configuration that allows the endpoint to accept JSON data:
<int:channel id="receiveChannel"/>
<http:inbound-channel-adapter id="restInputAdapter"
channel="receiveChannel"
path="/api/person"
request-payload-type="java.util.Map"
supported-methods="POST"/>
<jdbc:outbound-channel-adapter id="jdbcOutputAdapter"
channel="receiveChannel"
data-source="dataSource"
query='INSERT INTO "person" ("first_name", "last_name", "email_address") VALUES (:payload[firstName], :payload[lastName], :payload[email])'/>
This is in a Maven project with Jackson2 on the classpath, which is why no special configuration is required for reading JSON from the request.
However, attempting to post XML data results in the following exception:
org.springframework.messaging.MessagingException: Could not convert request: no suitable HttpMessageConverter found for expected type [java.util.Map] and content type [application/xml]]
I have tried using the message-converters attribute with http:inbound-channel-adapter, specifying Jackson, JAXB and Protocol Buffers converters explicitly but that does not help either.
I know how to do this in a bespoke Spring MVC application with #RestControllers so I am not looking for solutions outside of Spring Integration.
How can the Spring Integration configuration above be tweaked so that the REST endpoint can be made to accept JSON, XML and Google Protocol Buffers at the same time?

Answer 1

It seems that although JSON converts to java.util.Map, XML does not. This is why the seen error.
I created a class:
#XmlRootElement class Person { ... }
and then modified the configuration as follows (only changes shown):
<http:inbound-channel-adapter ...
request-payload-type="Person"
.../>
<jdbc:outbound-channel-adapter ...
query='INSERT INTO "person" ("first_name", "last_name", "email_address") VALUES (:payload.firstName, :payload.lastName, :payload.email)'
.../>
I can now post both XML and JSON data to the endpoint.
Google Protocol Buffers support can now be added using the Protostuff library.