SPR-5732 - When no type conversion strategy is found on a @Controller handler method bind target, a 500 error code should be returned not a 400.

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

@@ -23,6 +23,7 @@ import javax.servlet.http.HttpServletResponse;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.beans.ConversionNotSupportedException;
 import org.springframework.beans.TypeMismatchException;
 import org.springframework.core.Ordered;
 import org.springframework.http.MediaType;
@@ -95,6 +96,9 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 				return handleMissingServletRequestParameter((MissingServletRequestParameterException) ex, request,
 						response, handler);
 			}
+			else if (ex instanceof ConversionNotSupportedException) {
+				return handleConversionNotSupported((ConversionNotSupportedException) ex, request, response, handler);
+			}
 			else if (ex instanceof TypeMismatchException) {
 				return handleTypeMismatch((TypeMismatchException) ex, request, response, handler);
 			}
@@ -211,6 +215,27 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 		return new ModelAndView();
 	}
 
+	/**
+	 * Handle the case when a {@link org.springframework.web.bind.WebDataBinder} conversion cannot occur. <p>The default
+	 * implementation sends an HTTP 500 error, and returns an empty {@code ModelAndView}. Alternatively, a fallback view
+	 * could be chosen, or the TypeMismatchException could be rethrown as-is.
+	 *
+	 * @param ex the ConversionNotSupportedException 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 handleConversionNotSupported(ConversionNotSupportedException ex,
+			HttpServletRequest request,
+			HttpServletResponse response,
+			Object handler) throws Exception {
+		response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
+		return new ModelAndView();
+	}
+
 	/**
 	 * Handle the case when a {@link org.springframework.web.bind.WebDataBinder} conversion error occurs. <p>The default
 	 * implementation sends an HTTP 400 error, and returns an empty {@code ModelAndView}. Alternatively, a fallback view
@@ -228,7 +253,6 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 			HttpServletRequest request,
 			HttpServletResponse response,
 			Object handler) throws Exception {
-
 		response.sendError(HttpServletResponse.SC_BAD_REQUEST);
 		return new ModelAndView();
 	}

org.springframework.web.servlet/src/test/java/org/springframework/web/servlet/mvc/annotation/ServletAnnotationControllerTests.java

@@ -17,8 +17,8 @@
 package org.springframework.web.servlet.mvc.annotation;
 
 import java.io.IOException;
-import java.io.Writer;
 import java.io.Serializable;
+import java.io.Writer;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -106,6 +106,7 @@ import org.springframework.web.util.NestedServletException;
 /**
  * @author Juergen Hoeller
  * @author Sam Brannen
+ * @author Arjen Poutsma
  * @since 2.5
  */
 public class ServletAnnotationControllerTests {

org.springframework.web.servlet/src/test/java/org/springframework/web/servlet/mvc/annotation/UriTemplateServletAnnotationControllerTests.java

@@ -74,7 +74,18 @@ public class UriTemplateServletAnnotationControllerTests {
 		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/hotels/42/dates/2008-11-18");
 		MockHttpServletResponse response = new MockHttpServletResponse();
 		servlet.service(request, response);
-		assertEquals("test-42", response.getContentAsString());
+		assertEquals(200, response.getStatus());
+
+		request = new MockHttpServletRequest("GET", "/hotels/42/dates/2008-foo-bar");
+		response = new MockHttpServletResponse();
+		servlet.service(request, response);
+		assertEquals(400, response.getStatus());
+
+		initServlet(NonBindingUriTemplateController.class);
+		request = new MockHttpServletRequest("GET", "/hotels/42/dates/2008-foo-bar");
+		response = new MockHttpServletResponse();
+		servlet.service(request, response);
+		assertEquals(500, response.getStatus());
 	}
 
 	@Test
@@ -276,6 +287,16 @@ public class UriTemplateServletAnnotationControllerTests {
 
 	}
 
+	@Controller
+	public static class NonBindingUriTemplateController {
+
+		@RequestMapping("/hotels/{hotel}/dates/{date}")
+		public void handle(@PathVariable("hotel") String hotel, @PathVariable Date date, Writer writer)
+				throws IOException {
+		}
+
+	}
+
 	@Controller
 	@RequestMapping("/hotels/{hotel}")
 	public static class RelativePathUriTemplateController {