org.springframework.web.bind.support.WebRequestDataBinder Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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
*
* https://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.bind.support;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.Part;
import org.springframework.beans.MutablePropertyValues;
import org.springframework.lang.Nullable;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.util.StringUtils;
import org.springframework.validation.BindException;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.multipart.MultipartException;
import org.springframework.web.multipart.MultipartRequest;
/**
* Special {@link org.springframework.validation.DataBinder} to perform data binding
* from web request parameters to JavaBeans, including support for multipart files.
*
* See the DataBinder/WebDataBinder superclasses for customization options,
* which include specifying allowed/required fields, and registering custom
* property editors.
*
*
Can also used for manual data binding in custom web controllers or interceptors
* that build on Spring's {@link org.springframework.web.context.request.WebRequest}
* abstraction: e.g. in a {@link org.springframework.web.context.request.WebRequestInterceptor}
* implementation. Simply instantiate a WebRequestDataBinder for each binding
* process, and invoke {@code bind} with the current WebRequest as argument:
*
*
* MyBean myBean = new MyBean();
* // apply binder to custom target object
* WebRequestDataBinder binder = new WebRequestDataBinder(myBean);
* // register custom editors, if desired
* binder.registerCustomEditor(...);
* // trigger actual binding of request parameters
* binder.bind(request);
* // optionally evaluate binding errors
* Errors errors = binder.getErrors();
* ...
*
* @author Juergen Hoeller
* @author Brian Clozel
* @since 2.5.2
* @see #bind(org.springframework.web.context.request.WebRequest)
* @see #registerCustomEditor
* @see #setAllowedFields
* @see #setRequiredFields
* @see #setFieldMarkerPrefix
*/
public class WebRequestDataBinder extends WebDataBinder {
/**
* Create a new WebRequestDataBinder instance, with default object name.
* @param target the target object to bind onto (or {@code null}
* if the binder is just used to convert a plain parameter value)
* @see #DEFAULT_OBJECT_NAME
*/
public WebRequestDataBinder(@Nullable Object target) {
super(target);
}
/**
* Create a new WebRequestDataBinder instance.
* @param target the target object to bind onto (or {@code null}
* if the binder is just used to convert a plain parameter value)
* @param objectName the name of the target object
*/
public WebRequestDataBinder(@Nullable Object target, String objectName) {
super(target, objectName);
}
/**
* Bind the parameters of the given request to this binder's target,
* also binding multipart files in case of a multipart request.
* This call can create field errors, representing basic binding
* errors like a required field (code "required"), or type mismatch
* between value and bean property (code "typeMismatch").
*
Multipart files are bound via their parameter name, just like normal
* HTTP parameters: i.e. "uploadedFile" to an "uploadedFile" bean property,
* invoking a "setUploadedFile" setter method.
*
The type of the target property for a multipart file can be Part, MultipartFile,
* byte[], or String. The latter two receive the contents of the uploaded file;
* all metadata like original file name, content type, etc are lost in those cases.
* @param request the request with parameters to bind (can be multipart)
* @see org.springframework.web.multipart.MultipartRequest
* @see org.springframework.web.multipart.MultipartFile
* @see javax.servlet.http.Part
* @see #bind(org.springframework.beans.PropertyValues)
*/
public void bind(WebRequest request) {
MutablePropertyValues mpvs = new MutablePropertyValues(request.getParameterMap());
if (isMultipartRequest(request) && request instanceof NativeWebRequest) {
MultipartRequest multipartRequest = ((NativeWebRequest) request).getNativeRequest(MultipartRequest.class);
if (multipartRequest != null) {
bindMultipart(multipartRequest.getMultiFileMap(), mpvs);
}
else {
HttpServletRequest servletRequest = ((NativeWebRequest) request).getNativeRequest(HttpServletRequest.class);
if (servletRequest != null) {
bindParts(servletRequest, mpvs);
}
}
}
doBind(mpvs);
}
/**
* Check if the request is a multipart request (by checking its Content-Type header).
* @param request the request with parameters to bind
*/
private boolean isMultipartRequest(WebRequest request) {
String contentType = request.getHeader("Content-Type");
return StringUtils.startsWithIgnoreCase(contentType, "multipart");
}
private void bindParts(HttpServletRequest request, MutablePropertyValues mpvs) {
try {
MultiValueMap map = new LinkedMultiValueMap<>();
for (Part part : request.getParts()) {
map.add(part.getName(), part);
}
map.forEach((key, values) -> {
if (values.size() == 1) {
Part part = values.get(0);
if (isBindEmptyMultipartFiles() || part.getSize() > 0) {
mpvs.add(key, part);
}
}
else {
mpvs.add(key, values);
}
});
}
catch (Exception ex) {
throw new MultipartException("Failed to get request parts", ex);
}
}
/**
* Treats errors as fatal.
* Use this method only if it's an error if the input isn't valid.
* This might be appropriate if all input is from dropdowns, for example.
* @throws BindException if binding errors have been encountered
*/
public void closeNoCatch() throws BindException {
if (getBindingResult().hasErrors()) {
throw new BindException(getBindingResult());
}
}
}