Add ExceptionHandlerSupport class

The new class is functionally equivalent to the
DefaultHandlerExceptionResolver (i.e. it translates Spring MVC
exceptions to various status codes) but uses an @ExceptionHandler
returning a ResponseEntity<Object>, which means it can be customized to
write error content to the body of the response.

Issue: SPR-9290

Author: rstoyanchev

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

@@ -0,0 +1,397 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.servlet.mvc.method.annotation;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+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.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.converter.HttpMessageNotReadableException;
+import org.springframework.http.converter.HttpMessageNotWritableException;
+import org.springframework.util.CollectionUtils;
+import org.springframework.validation.BindException;
+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.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.context.request.WebRequest;
+import org.springframework.web.multipart.support.MissingServletRequestPartException;
+import org.springframework.web.servlet.mvc.multiaction.NoSuchRequestHandlingMethodException;
+
+/**
+ * A convenient base for classes with {@link ExceptionHandler} methods providing
+ * infrastructure to handle standard Spring MVC exceptions. The functionality is
+ * equivalent to that of the {@link DefaultHandlerExceptionResolver} except it
+ * can be customized to write error content to the body of the response. If there
+ * is no need to write error content, use {@code DefaultHandlerExceptionResolver}
+ * instead.
+ *
+ * <p>It is expected the sub-classes will be annotated with
+ * {@link ControllerAdvice @ControllerAdvice} and that
+ * {@link ExceptionHandlerExceptionResolver} is configured to ensure this class
+ * applies to exceptions from any {@link RequestMapping @RequestMapping} method.
+ *
+ * @author Rossen Stoyanchev
+ * @since 3.2
+ *
+ * @see org.springframework.web.servlet.mvc.support.DefaultHandlerExceptionResolver
+ */
+public abstract class ExceptionHandlerSupport {
+
+	protected final Log logger = LogFactory.getLog(getClass());
+
+	/**
+	 * Log category to use when no mapped handler is found for a request.
+	 * @see #pageNotFoundLogger
+	 */
+	public static final String PAGE_NOT_FOUND_LOG_CATEGORY = "org.springframework.web.servlet.PageNotFound";
+
+	/**
+	 * Additional logger to use when no mapped handler is found for a request.
+	 * @see #PAGE_NOT_FOUND_LOG_CATEGORY
+	 */
+	protected static final Log pageNotFoundLogger = LogFactory.getLog(PAGE_NOT_FOUND_LOG_CATEGORY);
+
+
+	/**
+	 * Provides handling for standard Spring MVC exceptions.
+	 * @param ex the target exception
+	 * @param request the current request
+	 */
+	@ExceptionHandler(value={
+			NoSuchRequestHandlingMethodException.class,
+			HttpRequestMethodNotSupportedException.class,
+			HttpMediaTypeNotSupportedException.class,
+			HttpMediaTypeNotAcceptableException.class,
+			MissingServletRequestParameterException.class,
+			ServletRequestBindingException.class,
+			ConversionNotSupportedException.class,
+			TypeMismatchException.class,
+			HttpMessageNotReadableException.class,
+			HttpMessageNotWritableException.class,
+			MethodArgumentNotValidException.class,
+			MissingServletRequestPartException.class,
+			BindException.class
+		})
+	public final ResponseEntity<Object> handleException(Exception ex, WebRequest request) {
+
+		HttpHeaders headers = new HttpHeaders();
+
+		HttpStatus status;
+		Object body;
+
+		if (ex instanceof NoSuchRequestHandlingMethodException) {
+			status = HttpStatus.NOT_FOUND;
+			body = handleNoSuchRequestHandlingMethod((NoSuchRequestHandlingMethodException) ex, headers, status, request);
+		}
+		else if (ex instanceof HttpRequestMethodNotSupportedException) {
+			status = HttpStatus.METHOD_NOT_ALLOWED;
+			body = handleHttpRequestMethodNotSupported((HttpRequestMethodNotSupportedException) ex, headers, status, request);
+		}
+		else if (ex instanceof HttpMediaTypeNotSupportedException) {
+			status = HttpStatus.UNSUPPORTED_MEDIA_TYPE;
+			body = handleHttpMediaTypeNotSupported((HttpMediaTypeNotSupportedException) ex, headers, status, request);
+		}
+		else if (ex instanceof HttpMediaTypeNotAcceptableException) {
+			status = HttpStatus.NOT_ACCEPTABLE;
+			body = handleHttpMediaTypeNotAcceptable((HttpMediaTypeNotAcceptableException) ex, headers, status, request);
+		}
+		else if (ex instanceof MissingServletRequestParameterException) {
+			status = HttpStatus.BAD_REQUEST;
+			body = handleMissingServletRequestParameter((MissingServletRequestParameterException) ex, headers, status, request);
+		}
+		else if (ex instanceof ServletRequestBindingException) {
+			status = HttpStatus.BAD_REQUEST;
+			body = handleServletRequestBindingException((ServletRequestBindingException) ex, headers, status, request);
+		}
+		else if (ex instanceof ConversionNotSupportedException) {
+			status = HttpStatus.INTERNAL_SERVER_ERROR;
+			body = handleConversionNotSupported((ConversionNotSupportedException) ex, headers, status, request);
+		}
+		else if (ex instanceof TypeMismatchException) {
+			status = HttpStatus.BAD_REQUEST;
+			body = handleTypeMismatch((TypeMismatchException) ex, headers, status, request);
+		}
+		else if (ex instanceof HttpMessageNotReadableException) {
+			status = HttpStatus.BAD_REQUEST;
+			body = handleHttpMessageNotReadable((HttpMessageNotReadableException) ex, headers, status, request);
+		}
+		else if (ex instanceof HttpMessageNotWritableException) {
+			status = HttpStatus.INTERNAL_SERVER_ERROR;
+			body = handleHttpMessageNotWritable((HttpMessageNotWritableException) ex, headers, status, request);
+		}
+		else if (ex instanceof MethodArgumentNotValidException) {
+			status = HttpStatus.BAD_REQUEST;
+			body = handleMethodArgumentNotValid((MethodArgumentNotValidException) ex, headers, status, request);
+		}
+		else if (ex instanceof MissingServletRequestPartException) {
+			status = HttpStatus.BAD_REQUEST;
+			body = handleMissingServletRequestPart((MissingServletRequestPartException) ex, headers, status, request);
+		}
+		else if (ex instanceof BindException) {
+			status = HttpStatus.BAD_REQUEST;
+			body = handleBindException((BindException) ex, headers, status, request);
+		}
+		else {
+			logger.warn("Unknown exception type: " + ex.getClass().getName());
+			status = HttpStatus.INTERNAL_SERVER_ERROR;
+			body = handleExceptionInternal(ex, headers, status, request);
+		}
+
+		return new ResponseEntity<Object>(body, headers, status);
+	}
+
+	/**
+	 * A single place to customize the response body of all Exception types.
+	 * This method returns {@code null} by default.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 */
+	protected Object handleExceptionInternal(Exception ex, HttpHeaders headers, HttpStatus status, WebRequest request) {
+		return null;
+	}
+
+	/**
+	 * Customize the response for NoSuchRequestHandlingMethodException.
+	 * This method logs a warning and delegates to
+	 * {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleNoSuchRequestHandlingMethod(NoSuchRequestHandlingMethodException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		pageNotFoundLogger.warn(ex.getMessage());
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for HttpRequestMethodNotSupportedException.
+	 * This method logs a warning, sets the "Allow" header, and delegates to
+	 * {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleHttpRequestMethodNotSupported(HttpRequestMethodNotSupportedException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		pageNotFoundLogger.warn(ex.getMessage());
+
+		Set<HttpMethod> mediaTypes = new HashSet<HttpMethod>();
+		for (String value : ex.getSupportedMethods()) {
+			mediaTypes.add(HttpMethod.valueOf(value));
+		}
+		if (!mediaTypes.isEmpty()) {
+			headers.setAllow(mediaTypes);
+		}
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for HttpMediaTypeNotSupportedException.
+	 * This method sets the "Accept" header and delegates to
+	 * {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleHttpMediaTypeNotSupported(HttpMediaTypeNotSupportedException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		List<MediaType> mediaTypes = ex.getSupportedMediaTypes();
+		if (!CollectionUtils.isEmpty(mediaTypes)) {
+			headers.setAccept(mediaTypes);
+		}
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for HttpMediaTypeNotAcceptableException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleHttpMediaTypeNotAcceptable(HttpMediaTypeNotAcceptableException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for MissingServletRequestParameterException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleMissingServletRequestParameter(MissingServletRequestParameterException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for ServletRequestBindingException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleServletRequestBindingException(ServletRequestBindingException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for ConversionNotSupportedException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleConversionNotSupported(ConversionNotSupportedException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for TypeMismatchException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleTypeMismatch(TypeMismatchException ex, HttpHeaders headers,
+			HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for HttpMessageNotReadableException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleHttpMessageNotReadable(HttpMessageNotReadableException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for HttpMessageNotWritableException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleHttpMessageNotWritable(HttpMessageNotWritableException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for MethodArgumentNotValidException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleMethodArgumentNotValid(MethodArgumentNotValidException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for MissingServletRequestPartException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleMissingServletRequestPart(MissingServletRequestPartException ex,
+			HttpHeaders headers, HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+	/**
+	 * Customize the response for BindException.
+	 * This method delegates to {@link #handleExceptionInternal(Exception, HttpHeaders, HttpStatus, WebRequest)}.
+	 * @param ex the exception
+	 * @param headers the headers to be written to the response
+	 * @param status the selected response status
+	 * @param request the current request
+	 * @return an Object or {@code null}
+	 */
+	protected Object handleBindException(BindException ex, HttpHeaders headers,
+			HttpStatus status, WebRequest request) {
+
+		return handleExceptionInternal(ex, headers, status, request);
+	}
+
+}