001/* 002 * Copyright 2002-2013 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.web.servlet.tags; 018 019import javax.servlet.ServletException; 020import javax.servlet.jsp.JspException; 021import javax.servlet.jsp.PageContext; 022 023import org.springframework.validation.Errors; 024 025/** 026 * JSP tag that evaluates content if there are binding errors 027 * for a certain bean. Exports an "errors" variable of type 028 * {@link org.springframework.validation.Errors} for the given bean. 029 * 030 * @author Rod Johnson 031 * @author Juergen Hoeller 032 * @see BindTag 033 * @see org.springframework.validation.Errors 034 */ 035@SuppressWarnings("serial") 036public class BindErrorsTag extends HtmlEscapingAwareTag { 037 038 public static final String ERRORS_VARIABLE_NAME = "errors"; 039 040 041 private String name; 042 043 private Errors errors; 044 045 046 /** 047 * Set the name of the bean that this tag should check. 048 */ 049 public void setName(String name) { 050 this.name = name; 051 } 052 053 /** 054 * Return the name of the bean that this tag checks. 055 */ 056 public String getName() { 057 return this.name; 058 } 059 060 061 @Override 062 protected final int doStartTagInternal() throws ServletException, JspException { 063 this.errors = getRequestContext().getErrors(this.name, isHtmlEscape()); 064 if (this.errors != null && this.errors.hasErrors()) { 065 this.pageContext.setAttribute(ERRORS_VARIABLE_NAME, this.errors, PageContext.REQUEST_SCOPE); 066 return EVAL_BODY_INCLUDE; 067 } 068 else { 069 return SKIP_BODY; 070 } 071 } 072 073 @Override 074 public int doEndTag() { 075 this.pageContext.removeAttribute(ERRORS_VARIABLE_NAME, PageContext.REQUEST_SCOPE); 076 return EVAL_PAGE; 077 } 078 079 /** 080 * Retrieve the Errors instance that this tag is currently bound to. 081 * <p>Intended for cooperating nesting tags. 082 */ 083 public final Errors getErrors() { 084 return this.errors; 085 } 086 087 088 @Override 089 public void doFinally() { 090 super.doFinally(); 091 this.errors = null; 092 } 093 094}