title: Spring boot: automatic JSON message converter for @Requestbody GET doesn't work
body: <p>Automatic message conversion is not for the next Rest.GET. How can I use automatic JSON message conversion? I read many different solutions without solving the important issue. </p>
  
  <p>Spring Boot is said to have a lot of standard message converters. </p>
  
  <p>Q1: Why is the message conversion failing? </p>
  
  <p>Q2: Should I really add the Jackson JSON converter to the message converter list? How?  </p>
  
  <p>The POJO object is: </p>
  
  <pre><code>public class CacheCoordinateRange {
      private double latitudeMin;
      private double latitudeMax;
      private double longitudeMin;
      private double longitudeMax;
  
      public CacheCoordinateRange() { }
      public CacheCoordinateRange( double latMin, double latMax, double lonMin, double lonMax) {
          this.latitudeMin = latMin;
          this.latitudeMax = latMax;
          this.longitudeMin = lonMin;
          this.longitudeMax = lonMax;
      }
      ... getters and setters
  </code></pre>
  
  <p>The Rest controller consists of: </p>
  
  <pre><code>@RequestMapping(method = RequestMethod.GET, value = "/coordinaterange", produces = { "application/json" }, consumes = MediaType.ALL_VALUE )
      public List&lt;Items&gt; findByCoordinateRange( @RequestBody CacheCoordinateRange coordinateRange) {
  return cacheRepository.findByLatitudeBetweenAndLongitudeBetween(  coordinateRange.getLatitudeMin(),
                  coordinateRange.getLatitudeMax(), coordinateRange.getLongitudeMin(), coordinateRange.getLongitudeMax());
      }
  </code></pre>
  
  <p>The rest(Test)Template is: </p>
  
  <pre><code>CacheCoordinateRange range = new CacheCoordinateRange(  52.023456, 52.223456, -12.0234562, -12.223456);
  HttpHeaders headersRange = new HttpHeaders();
  headersRange.setContentType(MediaType.APPLICATION_JSON);
  HttpEntity entityRange = new HttpEntity( range,headersRange);
  ResponseEntity&lt;SolvedCache[]&gt; resultRange = restTestTemplate.exchange(solvedCacheRestServices + "/coordinaterange", HttpMethod.GET, entityRange, SolvedCache[].class);
          objects = responseEntity.getBody();
  </code></pre>
  
  <p>The error is: </p>
  
  <pre><code>WARN org.springframework.web.servlet.mvc.support.DefaultHandlerExceptionResolver - Failed to read HTTP message: org.springframework.http.converter.HttpMessageNotReadableException: Required request body is missing: public java.util.List&lt;nl.xyz.caches.Cache&gt; nl.xyz.caches.SolvedCacheServices.findByCoordinateRange(nl.xyz.caches.CacheCoordinateRange)
  </code></pre>