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Java > Open Source Codes > com > jcorporate > expresso > ext > taglib > IfElementExists


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64
65 package com.jcorporate.expresso.ext.taglib;
66
67 /**
68  * IfElementExists.java
69  *
70  * Copyright 1999, 2000, 2001 Jcorporate Ltd.
71  */

72
73 import com.jcorporate.expresso.core.controller.Block;
74 import com.jcorporate.expresso.core.controller.ControllerElement;
75
76 import javax.servlet.jsp.JspTagException JavaDoc;
77 import javax.servlet.jsp.tagext.Tag JavaDoc;
78
79
80 /**
81  * @author Shash Chatterjee
82  */

83 public class IfElementExists
84         extends ExpressoTagSupport {
85     private ControllerElement oneElement = null;
86     private java.lang.String JavaDoc name = null;
87     private java.lang.String JavaDoc type = null;
88     private boolean inverse = false;
89     private java.lang.String JavaDoc nameToUse = null;
90
91     public IfElementExists() {
92         super();
93     }
94
95     public int doEndTag()
96             throws javax.servlet.jsp.JspTagException JavaDoc {
97         return EVAL_PAGE;
98     }
99
100     public int doStartTag()
101             throws javax.servlet.jsp.JspTagException JavaDoc {
102         getControllerResponse();
103         nameToUse = name;
104
105         try {
106             Tag JavaDoc container = getContainer();
107
108             if (container == null) {
109                 if (getType().equalsIgnoreCase("transition")) {
110                     oneElement = ctlrResp.getTransition(getName());
111                 } else if (getType().equalsIgnoreCase("block")) {
112                     oneElement = ctlrResp.getBlock(getName());
113                 } else if (getType().equalsIgnoreCase("input")) {
114                     oneElement = ctlrResp.getInput(getName());
115                 } else if (getType().equalsIgnoreCase("output")) {
116                     oneElement = ctlrResp.getOutput(getName());
117                 }
118             } else {
119                 if (container instanceof ElementIterator) {
120                     oneElement = ((ElementIterator) container).getElement();
121                     nameToUse = oneElement.getName();
122                 } else if (container instanceof BlockTag) {
123                     Block oneBlock = ((BlockTag) container).getBlock();
124
125                     if (oneBlock != null) {
126                         oneElement = oneBlock.getContent(getName());
127                     }
128                 } else {
129                     throw new JspTagException JavaDoc("Cannot handle container tag" +
130                             container.getClass().getName());
131                 }
132             }
133         } catch (Exception JavaDoc e) {
134             throw new JspTagException JavaDoc("IfElementExists Tag Error: " +
135                     e.getMessage());
136         }
137
138         boolean exists = true;
139
140         if (oneElement == null) {
141             exists = false;
142         }
143         if (inverse) {
144             exists = !exists;
145         }
146         if (exists) {
147             return EVAL_BODY_INCLUDE;
148         } else {
149             return SKIP_BODY;
150         }
151     }
152
153     public boolean getInverse() {
154         return this.inverse;
155     }
156
157     public java.lang.String JavaDoc getName() {
158         return nameToUse;
159     }
160
161     public java.lang.String JavaDoc getType() {
162         return type;
163     }
164
165     public void setInverse(boolean newInverse) {
166         this.inverse = newInverse;
167     }
168
169     public void setName(java.lang.String JavaDoc newName) {
170         name = newName;
171     }
172
173     public void setType(java.lang.String JavaDoc newType) {
174         type = newType;
175     }
176 } /* IfElementExists */
177
178 /* IfElementExists */
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