1 /* 2 * $Id: CheckLogonTag.java 471754 2006-11-06 14:55:09Z husted $ 3 * 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 22 23 package org.apache.struts.webapp.example2; 24 25 26 import javax.servlet.http.HttpSession; 27 import javax.servlet.jsp.JspException; 28 import javax.servlet.jsp.tagext.TagSupport; 29 30 31 /** 32 * Check for a valid User logged on in the current session. If there is no 33 * such user, forward control to the logon page. 34 * 35 * @author Craig R. McClanahan 36 * @author Marius Barduta 37 * @version $Rev: 471754 $ $Date: 2006-11-06 08:55:09 -0600 (Mon, 06 Nov 2006) $ 38 */ 39 40 public final class CheckLogonTag extends TagSupport { 41 42 43 // --------------------------------------------------- Instance Variables 44 45 46 /** 47 * The key of the session-scope bean we look for. 48 */ 49 private String name = Constants.USER_KEY; 50 51 52 /** 53 * The page to which we should forward for the user to log on. 54 */ 55 private String page = "/logon.jsp"; 56 57 58 // ----------------------------------------------------------- Properties 59 60 61 /** 62 * Return the bean name. 63 */ 64 public String getName() { 65 66 return (this.name); 67 68 } 69 70 71 /** 72 * Set the bean name. 73 * 74 * @param name The new bean name 75 */ 76 public void setName(String name) { 77 78 this.name = name; 79 80 } 81 82 83 /** 84 * Return the forward page. 85 */ 86 public String getPage() { 87 88 return (this.page); 89 90 } 91 92 93 /** 94 * Set the forward page. 95 * 96 * @param page The new forward page 97 */ 98 public void setPage(String page) { 99 100 this.page = page; 101 102 } 103 104 105 // ------------------------------------------------------- Public Methods 106 107 108 /** 109 * Defer our checking until the end of this tag is encountered. 110 * 111 * @exception JspException if a JSP exception has occurred 112 */ 113 public int doStartTag() throws JspException { 114 115 return (SKIP_BODY); 116 117 } 118 119 120 /** 121 * Perform our logged-in user check by looking for the existence of 122 * a session scope bean under the specified name. If this bean is not 123 * present, control is forwarded to the specified logon page. 124 * 125 * @exception JspException if a JSP exception has occurred 126 */ 127 public int doEndTag() throws JspException { 128 129 // Is there a valid user logged on? 130 boolean valid = false; 131 HttpSession session = pageContext.getSession(); 132 if ((session != null) && (session.getAttribute(name) != null)) 133 valid = true; 134 135 // Forward control based on the results 136 if (valid) 137 return (EVAL_PAGE); 138 else { 139 try { 140 pageContext.forward(page); 141 } catch (Exception e) { 142 throw new JspException(e.toString()); 143 } 144 return (SKIP_PAGE); 145 } 146 147 } 148 149 150 /** 151 * Release any acquired resources. 152 */ 153 public void release() { 154 155 super.release(); 156 this.name = Constants.USER_KEY; 157 this.page = "/logon.jsp"; 158 159 } 160 161 162 }