Add BindException to DefaultHandlerExceptionResolver

Previously DefaultHandlerExceptionResolver did not handle BindException
but after this change it does. A BindException is raised when an
@ModelAttribute annotated argument is not followed by a BindingResult
argument. Hence this is unlikely to affect browser rendering.
For programmatic clients however this change ensures an unhandled
BindException is at least turned into a 400 error.

Issue: SPR-9310

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

 /*
- * Copyright 2002-2010 the original author or authors.
+ * Copyright 2002-2012 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,12 +32,15 @@ import org.springframework.http.converter.HttpMessageNotReadableException;
 import org.springframework.http.converter.HttpMessageNotWritableException;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.StringUtils;
+import org.springframework.validation.BindException;
+import org.springframework.validation.BindingResult;
 import org.springframework.web.HttpMediaTypeNotAcceptableException;
 import org.springframework.web.HttpMediaTypeNotSupportedException;
 import org.springframework.web.HttpRequestMethodNotSupportedException;
 import org.springframework.web.bind.MethodArgumentNotValidException;
 import org.springframework.web.bind.MissingServletRequestParameterException;
 import org.springframework.web.bind.ServletRequestBindingException;
+import org.springframework.web.bind.annotation.ModelAttribute;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestPart;
 import org.springframework.web.multipart.MultipartFile;
@@ -65,6 +68,9 @@ import org.springframework.web.servlet.mvc.multiaction.NoSuchRequestHandlingMeth
  * @see #handleHttpMessageNotReadable
  * @see #handleHttpMessageNotWritable
  * @see #handleMethodArgumentNotValidException
+ * @see #handleMissingServletRequestParameter
+ * @see #handleMissingServletRequestPart
+ * @see #handleBindException
  */
 public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionResolver {
 
@@ -136,6 +142,9 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 			else if (ex instanceof MissingServletRequestPartException) {
 				return handleMissingServletRequestPartException((MissingServletRequestPartException) ex, request, response, handler);
 			}
+			else if (ex instanceof BindException) {
+				return handleBindException((BindException) ex, request, response, handler);
+			}
 		}
 		catch (Exception handlerException) {
 			logger.warn("Handling of [" + ex.getClass().getName() + "] resulted in Exception", handlerException);
@@ -346,8 +355,8 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 	}
 
 	/**
-	 * Handle the case where an argument annotated with {@code @Valid} such as 
-	 * an {@link RequestBody} or {@link RequestPart} argument fails validation. 
+	 * Handle the case where an argument annotated with {@code @Valid} such as
+	 * an {@link RequestBody} or {@link RequestPart} argument fails validation.
 	 * An HTTP 400 error is sent back to the client.
 	 * @param request current HTTP request
 	 * @param response current HTTP response
@@ -362,8 +371,8 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 	}
 
 	/**
-	 * Handle the case where an @{@link RequestPart}, a {@link MultipartFile}, 
-	 * or a {@code javax.servlet.http.Part} argument is required but missing. 
+	 * Handle the case where an {@linkplain RequestPart @RequestPart}, a {@link MultipartFile},
+	 * or a {@code javax.servlet.http.Part} argument is required but is missing.
 	 * An HTTP 400 error is sent back to the client.
 	 * @param request current HTTP request
 	 * @param response current HTTP response
@@ -377,4 +386,21 @@ public class DefaultHandlerExceptionResolver extends AbstractHandlerExceptionRes
 		return new ModelAndView();
 	}
 
+	/**
+	 * Handle the case where an {@linkplain ModelAttribute @ModelAttribute} method
+	 * argument has binding or validation errors and is not followed by another
+	 * method argument of type {@link BindingResult}.
+	 * By default an HTTP 400 error is sent back to the client.
+	 * @param request current HTTP request
+	 * @param response current HTTP response
+	 * @param handler the executed handler
+	 * @return an empty ModelAndView indicating the exception was handled
+	 * @throws IOException potentially thrown from response.sendError()
+	 */
+	protected ModelAndView handleBindException(BindException ex, HttpServletRequest request,
+			HttpServletResponse response, Object handler) throws IOException {
+		response.sendError(HttpServletResponse.SC_BAD_REQUEST);
+		return new ModelAndView();
+	}
+
 }

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/support/DefaultHandlerExceptionResolverTests.java

 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2012 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@ import org.springframework.http.converter.HttpMessageNotWritableException;
 import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.mock.web.MockHttpServletResponse;
 import org.springframework.validation.BeanPropertyBindingResult;
+import org.springframework.validation.BindException;
 import org.springframework.web.HttpMediaTypeNotSupportedException;
 import org.springframework.web.HttpRequestMethodNotSupportedException;
 import org.springframework.web.bind.MethodArgumentNotValidException;
@@ -157,6 +158,15 @@ public class DefaultHandlerExceptionResolverTests {
 		assertEquals("Invalid status code", 400, response.getStatus());
 	}
 
+	@Test
+	public void handleBindException() throws Exception {
+		BindException ex = new BindException(new Object(), "name");
+		ModelAndView mav = exceptionResolver.resolveException(request, response, null, ex);
+		assertNotNull("No ModelAndView returned", mav);
+		assertTrue("No Empty ModelAndView returned", mav.isEmpty());
+		assertEquals("Invalid status code", 400, response.getStatus());
+	}
+
 	public void handle(String arg) {
 	}
 

src/dist/changelog.txt

@@ -21,6 +21,7 @@ Changes in version 3.2 M2 (2012-08-xx)
 * add defaultCharset property to StringHttpMessageConverter
 * add @ExceptionResolver annotation to detect classes with @ExceptionHandler methods
 * move RSS/Atom message converter registration ahead of jackson/jaxb2
+* handle BindException in DefaultHandlerExceptionResolver
 
 
 Changes in version 3.2 M1 (2012-05-28)