SPR-5923 - HttpMessageConverter selection as a result of @ResponseBody should consider the requested content type

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/mvc/annotation/AnnotationMethodHandlerAdapter.java

@@ -20,6 +20,7 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.Reader;
 import java.io.Writer;
+import java.io.IOException;
 import java.lang.reflect.Method;
 import java.security.Principal;
 import java.util.ArrayList;
@@ -32,6 +33,7 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
+import java.util.Iterator;
 import java.util.concurrent.ConcurrentHashMap;
 import javax.servlet.ServletException;
 import javax.servlet.ServletRequest;
@@ -51,6 +53,7 @@ import org.springframework.core.ParameterNameDiscoverer;
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.http.HttpInputMessage;
 import org.springframework.http.HttpOutputMessage;
+import org.springframework.http.MediaType;
 import org.springframework.http.converter.BufferedImageHttpMessageConverter;
 import org.springframework.http.converter.ByteArrayHttpMessageConverter;
 import org.springframework.http.converter.FormHttpMessageConverter;
@@ -71,6 +74,7 @@ import org.springframework.util.StringUtils;
 import org.springframework.validation.support.BindingAwareModelMap;
 import org.springframework.web.HttpRequestMethodNotSupportedException;
 import org.springframework.web.HttpSessionRequiredException;
+import org.springframework.web.HttpMediaTypeNotAcceptableException;
 import org.springframework.web.bind.MissingServletRequestParameterException;
 import org.springframework.web.bind.ServletRequestDataBinder;
 import org.springframework.web.bind.WebDataBinder;
@@ -726,15 +730,7 @@ public class AnnotationMethodHandlerAdapter extends WebContentGenerator implemen
 			}
 
 			if (returnValue != null && handlerMethod.isAnnotationPresent(ResponseBody.class)) {
-				Class returnValueType = returnValue.getClass();
-				HttpOutputMessage outputMessage = new ServletServerHttpResponse(webRequest.getResponse());
-				for (HttpMessageConverter messageConverter : messageConverters) {
-					if (messageConverter.supports(returnValueType)) {
-						messageConverter.write(returnValue, outputMessage);
-						responseArgumentUsed = true;
-						return null;
-					}
-				}
+				handleRequestBody(returnValue, webRequest);
 			}
 
 			if (returnValue instanceof ModelAndView) {
@@ -777,6 +773,31 @@ public class AnnotationMethodHandlerAdapter extends WebContentGenerator implemen
 				throw new IllegalArgumentException("Invalid handler method return value: " + returnValue);
 			}
 		}
+
+		@SuppressWarnings("unchecked")
+		private void handleRequestBody(Object returnValue, ServletWebRequest webRequest) throws ServletException, IOException {
+			HttpInputMessage inputMessage = new ServletServerHttpRequest(webRequest.getRequest());
+			List<MediaType> acceptedMediaTypes = inputMessage.getHeaders().getAccept();
+			HttpOutputMessage outputMessage = new ServletServerHttpResponse(webRequest.getResponse());
+			Class<?> returnValueType = returnValue.getClass();
+			List<MediaType> allSupportedMediaTypes = new ArrayList<MediaType>();
+			for (HttpMessageConverter messageConverter : messageConverters) {
+				allSupportedMediaTypes.addAll(messageConverter.getSupportedMediaTypes());
+				if (messageConverter.supports(returnValueType)) {
+					for (Object o : messageConverter.getSupportedMediaTypes()) {
+						MediaType supportedMediaType = (MediaType) o;
+						for (MediaType acceptedMediaType : acceptedMediaTypes) {
+							if (supportedMediaType.includes(acceptedMediaType)) {
+								messageConverter.write(returnValue, outputMessage);
+								responseArgumentUsed = true;
+								return;
+							}
+						}
+					}
+				}
+			}
+			throw new HttpMediaTypeNotAcceptableException(allSupportedMediaTypes);
+		}
 	}
 
 	static class RequestMappingInfo {

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/mvc/support/DefaultHandlerExceptionResolver.java

@@ -33,6 +33,7 @@ import org.springframework.util.CollectionUtils;
 import org.springframework.util.StringUtils;
 import org.springframework.web.HttpMediaTypeNotSupportedException;
 import org.springframework.web.HttpRequestMethodNotSupportedException;
+import org.springframework.web.HttpMediaTypeNotAcceptableException;
 import org.springframework.web.bind.MissingServletRequestParameterException;
 import org.springframework.web.servlet.ModelAndView;
 import org.springframework.web.servlet.handler.AbstractHandlerExceptionResolver;
@@ -93,6 +94,10 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 				return handleHttpMediaTypeNotSupported((HttpMediaTypeNotSupportedException) ex, request, response,
 						handler);
 			}
+			else if (ex instanceof HttpMediaTypeNotAcceptableException) {
+				return handleHttpMediaTypeNotAcceptable((HttpMediaTypeNotAcceptableException) ex, request, response,
+						handler);
+			}
 			else if (ex instanceof MissingServletRequestParameterException) {
 				return handleMissingServletRequestParameter((MissingServletRequestParameterException) ex, request,
 						response, handler);
@@ -169,7 +174,7 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 
 	/**
 	 * Handle the case where no {@linkplain org.springframework.http.converter.HttpMessageConverter message converters}
-	 * were found for the PUT or POSTed content. <p>The default implementation sends an HTTP 415 error, sets the "Allow"
+	 * were found for the PUT or POSTed content. <p>The default implementation sends an HTTP 415 error, sets the "Accept"
 	 * header, and returns an empty {@code ModelAndView}. Alternatively, a fallback view could be chosen, or the
 	 * HttpMediaTypeNotSupportedException could be rethrown as-is.
 	 *
@@ -194,6 +199,29 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 		return new ModelAndView();
 	}
 
+	/**
+	 * Handle the case where no {@linkplain org.springframework.http.converter.HttpMessageConverter message converters}
+	 * were found that were acceptable for the client (expressed via the {@code Accept} header.
+	 * <p>The default implementation sends an HTTP 406 error and returns an empty {@code ModelAndView}. Alternatively,
+	 * a fallback view could be chosen, or the HttpMediaTypeNotAcceptableException could be rethrown as-is.
+	 *
+	 * @param ex the HttpMediaTypeNotAcceptableException to be handled
+	 * @param request current HTTP request
+	 * @param response current HTTP response
+	 * @param handler the executed handler, or <code>null</code> if none chosen at the time of the exception (for example,
+	 * if multipart resolution failed)
+	 * @return a ModelAndView to render, or <code>null</code> if handled directly
+	 * @throws Exception an Exception that should be thrown as result of the servlet request
+	 */
+	protected ModelAndView handleHttpMediaTypeNotAcceptable(HttpMediaTypeNotAcceptableException ex,
+			HttpServletRequest request,
+			HttpServletResponse response,
+			Object handler) throws Exception {
+
+		response.sendError(HttpServletResponse.SC_NOT_ACCEPTABLE);
+		return new ModelAndView();
+	}
+
 	/**
 	 * Handle the case when a required parameter is missing. <p>The default implementation sends an HTTP 400 error, and
 	 * returns an empty {@code ModelAndView}. Alternatively, a fallback view could be chosen, or the