title: REST-API Different Content-Type on Error Response
body: <p>Since some weeks I'm working on an rest api using spring-mvc.
  The REST-API is working properly and I`m almost done until one last problem when it comes to error handling with specific error-objects.</p>
  
  <p>The REST-API is using JSON as format to serialize Java-Objects. When an error occurs during service-execution an specific error-object gets created and sent back to the client.</p>
  
  <p>Everything is working fine when my rest-services are marked as "produces=application/json". But there are also some services which only need to return simple text using "produces=text/plain". 
  When an error occurs in one of these services Spring-MVC will throw an HttpMediaTypeNotAcceptableException. Seems to be correct cause client asks for content-type "text/plain" but server response with "application/json".</p>
  
  <p>Can you tell me what's the correct solution for this problem?</p>
  
  <ol>
  <li><p>Only using JSON as response content-type and wrapping simple text always in an special class object. => Seems to me not really REST like, cause REST should support multiple content-types.</p></li>
  <li><p>Every service serving "text" will be marked as "produces=application/json;text/plain" and Client also need to send both in "accept-header". => When doing it this way the API seems to support two content-types for same resource. But that`s not right. Only in case of an error the API will return JSON, otherwise it will be always "text".</p></li>
  </ol>
  
  <p>Sounds for me like a really special REST question and couldn`t find related questions on this topic.</p>