Revised validation javadoc, plus protected validate/isBindingErrorFatal template methods

Issue: SPR-12655
(cherry picked from commit 7585be8)

Author: jhoeller

spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/support/PayloadArgumentResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 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.
@@ -144,6 +144,16 @@ else if (payload instanceof String) {
 		}
 	}
 
+	/**
+	 * Validate the payload if applicable.
+	 * <p>The default implementation checks for {@code @javax.validation.Valid},
+	 * Spring's {@link org.springframework.validation.annotation.Validated},
+	 * and custom annotations whose name starts with "Valid".
+	 * @param message the currently processed message
+	 * @param parameter the method parameter
+	 * @param target the target payload object
+	 * @throws MethodArgumentNotValidException in case of binding errors
+	 */
 	protected void validate(Message<?> message, MethodParameter parameter, Object target) {
 		if (this.validator == null) {
 			return;

spring-web/src/main/java/org/springframework/web/method/annotation/ModelAttributeMethodProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 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.
@@ -56,7 +56,7 @@
  */
 public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResolver, HandlerMethodReturnValueHandler {
 
-	protected Log logger = LogFactory.getLog(this.getClass());
+	protected final Log logger = LogFactory.getLog(getClass());
 
 	private final boolean annotationNotRequired;
 
@@ -72,8 +72,8 @@ public ModelAttributeMethodProcessor(boolean annotationNotRequired) {
 
 
 	/**
-	 * @return true if the parameter is annotated with {@link ModelAttribute}
-	 * or in default resolution mode also if it is not a simple type.
+	 * Returns {@code true} if the parameter is annotated with {@link ModelAttribute}
+	 * or in default resolution mode, and also if it is not a simple type.
 	 */
 	@Override
 	public boolean supportsParameter(MethodParameter parameter) {
@@ -151,7 +151,9 @@ protected void bindRequestParameters(WebDataBinder binder, NativeWebRequest requ
 
 	/**
 	 * Validate the model attribute if applicable.
-	 * <p>The default implementation checks for {@code @javax.validation.Valid}.
+	 * <p>The default implementation checks for {@code @javax.validation.Valid},
+	 * Spring's {@link org.springframework.validation.annotation.Validated},
+	 * and custom annotations whose name starts with "Valid".
 	 * @param binder the DataBinder to be used
 	 * @param parameter the method parameter
 	 */

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/AbstractMessageConverterMethodArgumentResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2015 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.
@@ -37,6 +37,7 @@
 import org.springframework.http.converter.HttpMessageConverter;
 import org.springframework.http.server.ServletServerHttpRequest;
 import org.springframework.util.Assert;
+import org.springframework.validation.Errors;
 import org.springframework.web.HttpMediaTypeNotSupportedException;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
@@ -79,6 +80,7 @@ private static List<MediaType> getAllSupportedMediaTypes(List<HttpMessageConvert
 		return Collections.unmodifiableList(result);
 	}
 
+
 	/**
 	 * Create the method argument value of the expected parameter type by
 	 * reading from the given request.
@@ -162,4 +164,17 @@ protected ServletServerHttpRequest createInputMessage(NativeWebRequest webReques
 		return new ServletServerHttpRequest(servletRequest);
 	}
 
+	/**
+	 * Whether to raise a handler method invocation exception on validation errors.
+	 * @param parameter the method argument
+	 * @return {@code true} if the next method argument is not of type {@link Errors}
+	 * @since 4.1.5
+	 */
+	protected boolean isBindingErrorFatal(MethodParameter parameter) {
+		int i = parameter.getParameterIndex();
+		Class<?>[] paramTypes = parameter.getMethod().getParameterTypes();
+		boolean hasBindingResult = (paramTypes.length > (i + 1) && Errors.class.isAssignableFrom(paramTypes[i + 1]));
+		return !hasBindingResult;
+	}
+
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/RequestPartMethodArgumentResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 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.
@@ -222,7 +222,18 @@ private Class<?> getCollectionParameterType(MethodParameter parameter) {
 		return null;
 	}
 
-	private void validate(WebDataBinder binder, MethodParameter parameter) throws MethodArgumentNotValidException {
+	/**
+	 * Validate the request part if applicable.
+	 * <p>The default implementation checks for {@code @javax.validation.Valid},
+	 * Spring's {@link org.springframework.validation.annotation.Validated},
+	 * and custom annotations whose name starts with "Valid".
+	 * @param binder the DataBinder to be used
+	 * @param parameter the method parameter
+	 * @throws MethodArgumentNotValidException in case of a binding error which
+	 * is meant to be fatal (i.e. without a declared {@link Errors} parameter)
+	 * @see #isBindingErrorFatal
+	 */
+	protected void validate(WebDataBinder binder, MethodParameter parameter) throws MethodArgumentNotValidException {
 		Annotation[] annotations = parameter.getParameterAnnotations();
 		for (Annotation ann : annotations) {
 			Validated validatedAnn = AnnotationUtils.getAnnotation(ann, Validated.class);
@@ -240,18 +251,6 @@ private void validate(WebDataBinder binder, MethodParameter parameter) throws Me
 		}
 	}
 
-	/**
-	 * Whether to raise a {@link MethodArgumentNotValidException} on validation errors.
-	 * @param parameter the method argument
-	 * @return {@code true} if the next method argument is not of type {@link Errors}
-	 */
-	private boolean isBindingErrorFatal(MethodParameter parameter) {
-		int i = parameter.getParameterIndex();
-		Class<?>[] paramTypes = parameter.getMethod().getParameterTypes();
-		boolean hasBindingResult = (paramTypes.length > (i + 1) && Errors.class.isAssignableFrom(paramTypes[i + 1]));
-		return !hasBindingResult;
-	}
-
 
 	/**
 	 * Inner class to avoid hard-coded dependency on Servlet 3.0 Part type...

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/RequestResponseBodyMethodProcessor.java

@@ -112,7 +112,18 @@ public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer m
 		return argument;
 	}
 
-	private void validate(WebDataBinder binder, MethodParameter parameter) throws Exception {
+	/**
+	 * Validate the request part if applicable.
+	 * <p>The default implementation checks for {@code @javax.validation.Valid},
+	 * Spring's {@link org.springframework.validation.annotation.Validated},
+	 * and custom annotations whose name starts with "Valid".
+	 * @param binder the DataBinder to be used
+	 * @param parameter the method parameter
+	 * @throws MethodArgumentNotValidException in case of a binding error which
+	 * is meant to be fatal (i.e. without a declared {@link Errors} parameter)
+	 * @see #isBindingErrorFatal
+	 */
+	protected void validate(WebDataBinder binder, MethodParameter parameter) throws MethodArgumentNotValidException {
 		Annotation[] annotations = parameter.getParameterAnnotations();
 		for (Annotation ann : annotations) {
 			Validated validatedAnn = AnnotationUtils.getAnnotation(ann, Validated.class);
@@ -122,7 +133,7 @@ private void validate(WebDataBinder binder, MethodParameter parameter) throws Ex
 				binder.validate(validationHints);
 				BindingResult bindingResult = binder.getBindingResult();
 				if (bindingResult.hasErrors()) {
-					if (isBindExceptionRequired(binder, parameter)) {
+					if (isBindingErrorFatal(parameter)) {
 						throw new MethodArgumentNotValidException(parameter, bindingResult);
 					}
 				}
@@ -131,20 +142,6 @@ private void validate(WebDataBinder binder, MethodParameter parameter) throws Ex
 		}
 	}
 
-	/**
-	 * Whether to raise a {@link MethodArgumentNotValidException} on validation errors.
-	 * @param binder the data binder used to perform data binding
-	 * @param parameter the method argument
-	 * @return {@code true} if the next method argument is not of type {@link Errors}.
-	 */
-	private boolean isBindExceptionRequired(WebDataBinder binder, MethodParameter parameter) {
-		int i = parameter.getParameterIndex();
-		Class<?>[] paramTypes = parameter.getMethod().getParameterTypes();
-		boolean hasBindingResult = (paramTypes.length > (i + 1) && Errors.class.isAssignableFrom(paramTypes[i + 1]));
-
-		return !hasBindingResult;
-	}
-
 	@Override
 	protected <T> Object readWithMessageConverters(NativeWebRequest webRequest,
 			MethodParameter methodParam,  Type paramType) throws IOException, HttpMediaTypeNotSupportedException {