Java tutorial
/* * Copyright 2002-2008 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 com.laxser.blitz.web.paramresolver; import java.util.Date; import javax.servlet.ServletRequest; import org.springframework.beans.BeanUtils; import org.springframework.beans.MutablePropertyValues; import org.springframework.beans.PropertyEditorRegistry; import org.springframework.beans.PropertyValue; import org.springframework.validation.AbstractPropertyBindingResult; import org.springframework.validation.BindException; import org.springframework.web.bind.ServletRequestBindingException; import org.springframework.web.bind.WebDataBinder; import org.springframework.web.multipart.MultipartHttpServletRequest; import org.springframework.web.util.WebUtils; import com.laxser.blitz.web.paramresolver.ResolverFactoryImpl.DateEditor; /** * Special {@link org.springframework.validation.DataBinder} to perform * data binding from servlet request parameters to JavaBeans, including * support for multipart files. * * <p> * See the DataBinder/WebDataBinder superclasses for customization options, * which include specifying allowed/required fields, and registering custom * property editors. * * <p> * Used by Spring Web MVC's BaseCommandController and * MultiActionController. Note that BaseCommandController and its * subclasses allow for easy customization of the binder instances that * they use through overriding <code>initBinder</code>. * * <p> * Can also be used for manual data binding in custom web controllers: for * example, in a plain Controller implementation or in a * MultiActionController handler method. Simply instantiate a * ServletRequestDataBinder for each binding process, and invoke * <code>bind</code> with the current ServletRequest as argument: * * <pre class="code"> MyBean myBean = new MyBean(); // apply binder to * custom target object ServletRequestDataBinder binder = new * ServletRequestDataBinder(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(); ...</pre> * * @author Rod Johnson * @author Juergen Hoeller * @see #bind(javax.servlet.ServletRequest) * @see #registerCustomEditor * @see #setAllowedFields * @see #setRequiredFields * @see #setFieldMarkerPrefix * @see org.springframework.web.servlet.mvc.BaseCommandController#initBinder */ public class ServletRequestDataBinder extends WebDataBinder { private String prefix; /** * Create a new ServletRequestDataBinder instance, with default object * name. * * @param target the target object to bind onto (or <code>null</code> * if the binder is just used to convert a plain parameter * value) * @see #DEFAULT_OBJECT_NAME */ public ServletRequestDataBinder(Object target) { super(target); } /** * Create a new ServletRequestDataBinder instance. * * @param target the target object to bind onto (or <code>null</code> * if the binder is just used to convert a plain parameter * value) * @param objectName the name of the target object */ public ServletRequestDataBinder(Object target, String objectName) { super(target, objectName); prefix = objectName + '.'; } /** * Return the internal BindingResult held by this DataBinder, as * AbstractPropertyBindingResult. */ @Override protected AbstractPropertyBindingResult getInternalBindingResult() { AbstractPropertyBindingResult bindingResult = super.getInternalBindingResult(); // by blitz PropertyEditorRegistry registry = bindingResult.getPropertyEditorRegistry(); registry.registerCustomEditor(Date.class, new DateEditor(Date.class)); registry.registerCustomEditor(java.sql.Date.class, new DateEditor(java.sql.Date.class)); registry.registerCustomEditor(java.sql.Time.class, new DateEditor(java.sql.Time.class)); registry.registerCustomEditor(java.sql.Timestamp.class, new DateEditor(java.sql.Timestamp.class)); return bindingResult; } /** * Bind the parameters of the given request to this binder's target, * also binding multipart files in case of a multipart request. * <p> * 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"). * <p> * 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. * <p> * The type of the target property for a multipart file can be * 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 request with parameters to bind (can be multipart) * @see org.springframework.web.multipart.MultipartHttpServletRequest * @see org.springframework.web.multipart.MultipartFile * @see #bindMultipartFiles * @see #bind(org.springframework.beans.PropertyValues) */ public void bind(ServletRequest request) { MutablePropertyValues mpvs = new MutablePropertyValues(WebUtils.getParametersStartingWith(request, prefix)); if (request instanceof MultipartHttpServletRequest) { MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; bindMultipartFiles(multipartRequest.getFileMap(), mpvs); } doBind(mpvs); } @Override protected void doBind(MutablePropertyValues mpvs) { // book.author.name?book.authorauthor PropertyValue[] pvArray = mpvs.getPropertyValues(); MutablePropertyValues newMpvs = null; for (int i = 0; i < pvArray.length; i++) { PropertyValue pv = pvArray[i]; String propertyName = pv.getName(); int dot = propertyName.indexOf('.'); while (dot != -1) { String field = propertyName.substring(0, dot); if (getPropertyAccessor().isWritableProperty(field) && !mpvs.contains(field)) { Class<?> fieldType = getPropertyAccessor().getPropertyType(field); if (newMpvs == null) { newMpvs = new MutablePropertyValues(); } newMpvs.addPropertyValue(field, BeanUtils.instantiateClass(fieldType)); } dot = propertyName.indexOf('.', dot + 1); } } if (newMpvs == null) { super.doBind(mpvs); } else { newMpvs.addPropertyValues(mpvs); super.doBind(newMpvs); } } /** * Treats errors as fatal. * <p> * 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 ServletRequestBindingException subclass of ServletException * on any binding problem */ public void closeNoCatch() throws ServletRequestBindingException { if (getBindingResult().hasErrors()) { throw new ServletRequestBindingException( "Errors binding onto object '" + getBindingResult().getObjectName() + "'", new BindException(getBindingResult())); } } }