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Java > Open Source Codes > com > jcorporate > expresso > ext > struts > taglib > logic > ExPresentTag


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64
65 package com.jcorporate.expresso.ext.struts.taglib.logic;
66
67 import com.jcorporate.expresso.core.misc.StringUtil;
68 import com.jcorporate.expresso.ext.struts.taglib.ControllerUtils;
69 import org.apache.log4j.Logger;
70 import org.apache.struts.taglib.logic.PresentTag;
71 import org.apache.struts.util.RequestUtils;
72
73 import javax.servlet.http.Cookie JavaDoc;
74 import javax.servlet.http.HttpServletRequest JavaDoc;
75 import javax.servlet.jsp.JspException JavaDoc;
76 import java.security.Principal JavaDoc;
77
78
79 /**
80  * Evalute the nested body content of this tag if the specified value
81  * is present for this request.
82  * <p/>
83  * THIS TAG ASSUMES A 'CONTROLLER CONTEXT' AND DOES NOT WORK IF CALLED
84  * IN A 'NAKED' JSP
85  *
86  * @author Craig R. McClanahan
87  */
88 public class ExPresentTag
89         extends PresentTag {
90     private static Logger log = Logger.getLogger("expresso.ext.struts.taglib.logic.ExPresentTag");
91
92     /**
93      * Evaluate the condition that is being tested by this particular tag,
94      * and return <code>true</code> if the nested body content of this tag
95      * should be evaluated, or <code>false</code> if it should be skipped.
96      * This method must be implemented by concrete subclasses.
97      *
98      * @param desired Desired outcome for a true result
99      * @return integer as specified by the JSP Taglib spec
100      * @throws JspException if a JSP exception occurs
101      */
102     protected boolean condition(boolean desired)
103             throws JspException JavaDoc {
104         if (log.isDebugEnabled()) {
105             log.debug("ExPresentTag begins");
106         }
107
108         String JavaDoc nameToUse = name;
109         String JavaDoc propertyToUse = property;
110
111         // Evaluate the presence of the specified value
112 boolean present = false;
113
114         if (cookie != null) {
115             Cookie JavaDoc[] cookies = ((HttpServletRequest JavaDoc) pageContext.getRequest()).getCookies();
116
117             if (cookies == null) {
118                 cookies = new Cookie JavaDoc[0];
119             }
120             for (int i = 0; i < cookies.length; i++) {
121                 if (cookie.equals(cookies[i].getName())) {
122                     present = true;
123                     break;
124                 }
125             }
126         } else if (header != null) {
127             String JavaDoc value = ((HttpServletRequest JavaDoc) pageContext.getRequest()).getHeader(header);
128             present = (value != null);
129         } else if (nameToUse != null) {
130             if (log.isDebugEnabled()) {
131                 log.debug("Name is not null - looking for property '" +
132                         StringUtil.notNull(propertyToUse) + "' in bean '" +
133                         StringUtil.notNull(nameToUse) + "'");
134             }
135
136             present = ControllerUtils.exists(pageContext, nameToUse,
137                     propertyToUse);
138         } else if (propertyToUse != null) {
139             if (log.isDebugEnabled()) {
140                 log.debug("Property is not null - looking for property '" +
141                         StringUtil.notNull(propertyToUse) + "' in bean '" +
142                         StringUtil.notNull(nameToUse) + "'");
143             }
144
145             present = ControllerUtils.exists(pageContext, nameToUse,
146                     propertyToUse);
147         } else if (parameter != null) {
148             String JavaDoc value = pageContext.getRequest().getParameter(parameter);
149             present = (value != null);
150         } else if (role != null) {
151             HttpServletRequest JavaDoc request = (HttpServletRequest JavaDoc) pageContext.getRequest();
152             present = request.isUserInRole(role);
153         } else if (user != null) {
154             HttpServletRequest JavaDoc request = (HttpServletRequest JavaDoc) pageContext.getRequest();
155             Principal JavaDoc principal = request.getUserPrincipal();
156             present = (principal != null) &&
157                     user.equals(principal.getName());
158         } else {
159             JspException JavaDoc e = new JspException JavaDoc(messages.getMessage("logic.selector"));
160             RequestUtils.saveException(pageContext, e);
161             throw e;
162         }
163
164         return (present == desired);
165     }
166 }
167
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