/*
* Copyright 2002-2017 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.List;
import javax.servlet.http.HttpServletRequest;
import org.springframework.core.MethodParameter;
import org.springframework.http.HttpInputMessage;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.ModelAndViewContainer;
import org.springframework.web.multipart.MultipartException;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartResolver;
import org.springframework.web.multipart.support.MissingServletRequestPartException;
import org.springframework.web.multipart.support.MultipartResolutionDelegate;
import org.springframework.web.multipart.support.RequestPartServletServerHttpRequest;
/**
* Resolves the following method arguments:
* <ul>
* <li>Annotated with {@code @RequestPart}
* <li>Of type {@link MultipartFile} in conjunction with Spring's {@link MultipartResolver} abstraction
* <li>Of type {@code javax.servlet.http.Part} in conjunction with Servlet 3.0 multipart requests
* </ul>
*
* <p>When a parameter is annotated with {@code @RequestPart}, the content of the part is
* passed through an {@link HttpMessageConverter} to resolve the method argument with the
* 'Content-Type' of the request part in mind. This is analogous to what @{@link RequestBody}
* does to resolve an argument based on the content of a regular request.
*
* <p>When a parameter is not annotated or the name of the part is not specified,
* it is derived from the name of the method argument.
*
* <p>Automatic validation may be applied if the argument is annotated with
* {@code @javax.validation.Valid}. In case of validation failure, a {@link MethodArgumentNotValidException}
* is raised and a 400 response status code returned if
* {@link org.springframework.web.servlet.mvc.support.DefaultHandlerExceptionResolver} is configured.
*
* @author Rossen Stoyanchev
* @author Brian Clozel
* @author Juergen Hoeller
* @since 3.1
*/
public class RequestPartMethodArgumentResolver extends AbstractMessageConverterMethodArgumentResolver {
/**
* Basic constructor with converters only.
*/
public RequestPartMethodArgumentResolver(List<HttpMessageConverter<?>> messageConverters) {
super(messageConverters);
}
/**
* Constructor with converters and {@code Request~} and
* {@code ResponseBodyAdvice}.
*/
public RequestPartMethodArgumentResolver(List<HttpMessageConverter<?>> messageConverters,
List<Object> requestResponseBodyAdvice) {
super(messageConverters, requestResponseBodyAdvice);
}
/**
* Supports the following:
* <ul>
* <li>annotated with {@code @RequestPart}
* <li>of type {@link MultipartFile} unless annotated with {@code @RequestParam}
* <li>of type {@code javax.servlet.http.Part} unless annotated with {@code @RequestParam}
* </ul>
*/
@Override
public boolean supportsParameter(MethodParameter parameter) {
if (parameter.hasParameterAnnotation(RequestPart.class)) {
return true;
}
else {
if (parameter.hasParameterAnnotation(RequestParam.class)) {
return false;
}
return MultipartResolutionDelegate.isMultipartArgument(parameter.nestedIfOptional());
}
}
@Override
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
NativeWebRequest request, WebDataBinderFactory binderFactory) throws Exception {
HttpServletRequest servletRequest = request.getNativeRequest(HttpServletRequest.class);
RequestPart requestPart = parameter.getParameterAnnotation(RequestPart.class);
boolean isRequired = ((requestPart == null || requestPart.required()) && !parameter.isOptional());
String name = getPartName(parameter, requestPart);
parameter = parameter.nestedIfOptional();
Object arg = null;
Object mpArg = MultipartResolutionDelegate.resolveMultipartArgument(name, parameter, servletRequest);
if (mpArg != MultipartResolutionDelegate.UNRESOLVABLE) {
arg = mpArg;
}
else {
try {
HttpInputMessage inputMessage = new RequestPartServletServerHttpRequest(servletRequest, name);
arg = readWithMessageConverters(inputMessage, parameter, parameter.getNestedGenericParameterType());
WebDataBinder binder = binderFactory.createBinder(request, arg, name);
if (arg != null) {
validateIfApplicable(binder, parameter);
if (binder.getBindingResult().hasErrors() && isBindExceptionRequired(binder, parameter)) {
throw new MethodArgumentNotValidException(parameter, binder.getBindingResult());
}
}
mavContainer.addAttribute(BindingResult.MODEL_KEY_PREFIX + name, binder.getBindingResult());
}
catch (MissingServletRequestPartException ex) {
if (isRequired) {
throw ex;
}
}
catch (MultipartException ex) {
if (isRequired) {
throw ex;
}
}
}
if (arg == null && isRequired) {
if (!MultipartResolutionDelegate.isMultipartRequest(servletRequest)) {
throw new MultipartException("Current request is not a multipart request");
}
else {
throw new MissingServletRequestPartException(name);
}
}
return adaptArgumentIfNecessary(arg, parameter);
}
private String getPartName(MethodParameter methodParam, RequestPart requestPart) {
String partName = (requestPart != null ? requestPart.name() : "");
if (partName.isEmpty()) {
partName = methodParam.getParameterName();
if (partName == null) {
throw new IllegalArgumentException("Request part name for argument type [" +
methodParam.getNestedParameterType().getName() +
"] not specified, and parameter name information not found in class file either.");
}
}
return partName;
}
}