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1   /*
2    * Copyright 2004 The Apache Software Foundation.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    *     http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   *
16   * $Header:$
17   */
18  package org.apache.beehive.netui.tags.template;
19  
20  import org.apache.beehive.netui.util.internal.InternalStringBuilder;
21  
22  import org.apache.beehive.netui.tags.AbstractClassicTag;
23  import org.apache.beehive.netui.tags.javascript.IScriptReporter;
24  import org.apache.beehive.netui.tags.javascript.ScriptRequestState;
25  import org.apache.beehive.netui.tags.divpanel.DivPanel;
26  import org.apache.beehive.netui.tags.databinding.repeater.Repeater;
27  import org.apache.beehive.netui.util.Bundle;
28  
29  import javax.servlet.ServletRequest  ;
30  import javax.servlet.http.HttpServletRequest  ;
31  import javax.servlet.jsp.JspException  ;
32  import javax.servlet.jsp.tagext.BodyContent  ;
33  import javax.servlet.jsp.tagext.Tag  ;
34  import java.util.HashMap  ;
35  
36  import org.apache.struts.util.ResponseUtils;
37  
38  /**
39   * Used within a content page to provide content for a placeholder
40   * section defined within a template.  The body content of the tag
41   * is passed to the <code>IncludeSection</code> tag in the template
42   * providing the content for that section.
43   * If the <code>name</code> attribute matches a
44   * <code>name</code> attribute on a
45   * <code>IncludeSection</code> tag in the template, the body
46   * content of this tag will be rendered.
47  
48   * @jsptagref.tagdescription
49   * Sets HTML content inside placeholders defined by a 
50   * {@link  IncludeSection} tag.
51   * 
52   * <p>The &lt;netui-template:section> tag must have a parent 
53   * {@link Template} tag. 
54   * 
55   * <p>The &lt;netui-template:section> tag appears in content pages, which adopt a template page, 
56   * set properties on the template's placeholders 
57   * (using this &lt;netui-template:section> tag), 
58   * and render the completed HTML in the browser.
59   * 
60   * <p>For content to be placed in the placeholder, the &lt;netui-template:section> and 
61   * &lt;netui-template:includeSection> tags must have matching <code>name</code> attributes.
62   * 
63   * <p>For example, assume a template page defines the following content placeholder.
64   * 
65   * <p><b>In the template JSP page...</b>
66   * 
67   * <pre>      &lt;table>
68   *          &lt;tr>
69   *              &lt;td colspan="3">
70   *                  &lt;netui-template:includeSection name="tableHeader"/>
71   *              &lt;/td>
72   *          &lt;/tr></pre>
73   * 
74   * <p>Then a content page can set HTML content in the placeholder using the &lt;netui-template:section> tag.
75   * 
76   * <p><b>In a content JSP page...</b>
77   * 
78   * <pre>    &lt;netui-template:section name="tableHeader">
79   *        &lt;h1>HEADER TEXT&lt;/h1>
80   *    &lt;/netui-template:section></pre>
81   * 
82   * <p>The HTML rendered in the browser will appear as follows.
83   * 
84   * <pre>      &lt;table>
85   *          &lt;tr>
86   *              &lt;td colspan="3">
87   *                  &lt;h1>HEADER TEXT&lt;/h1>
88   *              &lt;/td>
89   *          &lt;/tr></pre>
90   * 
91   * @example 
92   * Assume a &lt;netui-template:includeSection> tag defines a content placeholder inside a 
93   * table row 
94   *
95   * <pre>    &lt;tr>
96   *        &lt;netui-template:includeSection name="rowPlaceholder"/>
97   *    &lt;/tr></pre>
98   *    
99   * <p>A content page can set content into the placeholder using the &lt;netui-template:section> 
100  * tag as follows.
101  * 
102  * <pre>  &lt;netui-template:section name="rowPlaceHolder">
103  *      &lt;td>&lt;p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit, 
104  *      sed diam nonummy nibh euismod tincidunt ut laoreet dolore 
105  *      magna aliquam erat volutpat. Ut wisi enim ad minim veniam, 
106  *      quis nostrud exerci tation ullamcorper suscipit lobortis nisl 
107  *      ut aliquip ex ea commodo consequat.&lt;/p>&lt;/td>
108  *  &lt;/netui-template:section></pre>
109  * 
110  * The HTML rendered in the browser will appear as follows.
111  * 
112  * <pre>    &lt;tr>
113  *      &lt;td>&lt;p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit, 
114  *      sed diam nonummy nibh euismod tincidunt ut laoreet dolore 
115  *      magna aliquam erat volutpat. Ut wisi enim ad minim veniam, 
116  *      quis nostrud exerci tation ullamcorper suscipit lobortis nisl 
117  *      ut aliquip ex ea commodo consequat.&lt;/p>&lt;/td>
118  *    &lt;/tr></pre>
119  *    
120  * @netui:tag name="section"
121  *          description="Use this tag to mark out content to replace a netui-template:includeSection within a template file."
122  */
123 public class Section extends AbstractClassicTag
124         implements TemplateConstants
125 {
126     /**
127      * The name of the section.
128      */
129     private String   _name;
130 
131     /**
132      * Is the section visible
133      */
134     private boolean _visible = true;
135 
136     /**
137      * Returns the name of the Tag.  This is used to
138      * identify the type of tag reporting errors.
139      * @return a constant string representing the name of the tag.
140      */
141     public String   getTagName() {
142         return "Section";
143     }
144 
145     /**
146      * Sets the name of the placeholder section defined in
147      * the template that this tag is providing content for.
148      * This name is matched against the <code>IncludeSection</code>
149      * name.  If the names match, the content of this tag will be
150      * rendered within the template's section.
151      * @param name The name of an <code>IncludeSection<code> the
152      * this tag is providing content for.
153      *
154      * @jsptagref.attributedescription
155      * The name of the content to fill the placeholder. 
156      * This name is matched against the &lt;netui-template:includeSection>
157      * name.  If the names match, the content of this tag will be
158      * rendered within the template's placeholder.
159      * 
160      * @jsptagref.databindable false
161      * 
162      * @jsptagref.attributesyntaxvalue <i>string_name</i>
163      *
164      * @netui:attribute required="true" rtexprvalue="true"
165      * description="The name of the content to fill the placeholder."
166      */
167     public void setName(String   name) {
168         _name = name;
169     }
170 
171     /**
172      * Sets the visible state of the tag.
173      * @param visible <code>Boolean</code> value representing the visible state.
174      *
175      * @jsptagref.attributedescription
176      * Boolean. Determines if the section is visible.
177      * 
178      * @jsptagref.databindable false
179      * 
180      * @jsptagref.attributesyntaxvalue <i>boolean_literal_visible</i>
181      *
182      * @netui:attribute required="false" rtexprvalue="true" type="boolean"
183      * description="Determines if the section is visible."
184      */
185     public void setVisible(boolean visible) {
186         _visible = visible;
187     }
188 
189     /**
190      * Causes the content of the section to be rendered into a buffer.
191      * @return SKIP_BODY if the visible state is <code>false</code>,
192      *  otherwise EVAL_BODY_BUFFERED to cause the body content to be buffered.
193      * @throws JspException if there are errors.
194      */
195     public int doStartTag()
196             throws JspException   {
197 
198         if (!_visible)
199             return SKIP_BODY;
200 
201         // If the parent is a DivPanel then this section will be inlined.
202         Tag parentTag = getParent();
203         // If the parent tag is a repeater then we must insure that the parent of that is a DivPanel
204         if (parentTag instanceof Repeater) {
205             parentTag = parentTag.getParent();
206             if (!(parentTag instanceof DivPanel)) {
207                 String   s = Bundle.getString("Temp_SectionInRepeater");
208                 registerTagError(s,null);
209                 reportErrors();
210                 localRelease();
211                 return EVAL_PAGE;
212              }
213         }
214         if (parentTag instanceof DivPanel) {
215             InternalStringBuilder results = new InternalStringBuilder(128);
216             results.append("<div ");
217             renderTagId(results);
218             if (hasErrors()) {
219                 reportErrors();
220                 localRelease();
221                 return EVAL_PAGE;
222             }
223             results.append(">");
224             ResponseUtils.write(pageContext,results.toString());
225             return EVAL_BODY_BUFFERED;
226         }
227 
228         return EVAL_BODY_BUFFERED;
229     }
230 
231     /**
232      * Stores the buffered body content into the <code>TEMPLATE_SECTIONS
233      * HashMap</code>.  The buffered body is
234      * accessed by the template page to obtain
235      * the content for <code>IncludeSection</code> tags.
236      * @return EVAL_PAGE to continue evaluating the page.
237      * @throws JspException on error.
238      */
239     public int doEndTag()
240             throws JspException   {
241 
242         // If the parent is a DivPanel then this section will be inlined.
243         Tag parentTag = getParent();
244         if (parentTag instanceof Repeater) {
245              parentTag = parentTag.getParent();
246         }
247          if (parentTag instanceof DivPanel) {
248             return processDivPanel();
249         }
250         assert(parentTag instanceof Template);
251         return processTemplate();
252     }
253 
254     /**
255      * Resets all of the fields of the tag.
256      */
257     protected void localRelease() {
258         super.localRelease();
259         _name = null;
260         _visible = true;
261     }
262 
263     /**
264      * This method will process the section in the context of a DivPanel
265      * @return returns the integer code doEndTag() will return.
266      */
267     private int processDivPanel()
268             throws JspException   {
269 
270         if (!_visible)
271             return EVAL_PAGE;
272 
273         if (hasErrors()) {
274             reportErrors();
275             localRelease();
276             return EVAL_PAGE;
277         }
278 
279         BodyContent   bc = getBodyContent();
280         String   content = (bc != null) ? bc.getString() : "";
281         ResponseUtils.write(pageContext,content);
282         ResponseUtils.write(pageContext,"</div>");
283         localRelease();
284         return EVAL_PAGE;
285     }
286 
287     /**
288      * THis method will process the section in the context of the Template
289      * @return returns the integer code doEndTag() will return.
290      */
291     private int processTemplate()
292     {
293         ServletRequest   req = pageContext.getRequest();
294         Template.TemplateContext tc = (Template.TemplateContext)
295                 req.getAttribute(TEMPLATE_SECTIONS);
296 
297         if (tc.secs == null) {
298             tc.secs = new HashMap  ();
299         }
300 
301         assert (tc.secs != null);
302 
303         if (!_visible) {
304             // set the section so that it doesn't contain anything
305             tc.secs.put(_name,"");
306             localRelease();
307             return EVAL_PAGE;
308         }
309         if (hasErrors()) {
310             String   s = getErrorsReport();
311             tc.secs.put(_name,s);
312             localRelease();
313             return EVAL_PAGE;
314         }
315 
316         BodyContent   bc = getBodyContent();
317         String   content = (bc != null) ? bc.getString() : "";
318         tc.secs.put(_name,content);
319         localRelease();
320         return EVAL_PAGE;
321     }
322 
323     // @TODO: this code is duplicated between section and divPanel
324     /**
325      * This method will handle creating the tagId attribute.  The tagId attribute indentifies the
326      * tag in the generated HTML.  There is a lookup table created in JavaScript mapping the <coe>tagId</code>
327      * to the actual name.  The tagId is also run through the naming service so it can be scoped.  Some tags will
328      * write that <code>tagid</code> out as the <code>id</code> attribute of the HTML tag being generated.
329      * @param buffer
330      * @return String
331      */
332     private final String   renderTagId(InternalStringBuilder buffer)
333         throws JspException   {
334         assert(_name != null);
335 
336         // @todo: this is busted.  It should be writing out inline.
337         String   realName = rewriteName(_name);
338         String   idScript = mapLegacyTagId(_name, realName);
339 
340         // some tags will output the id attribute themselves so they don't write this out
341         renderAttribute(buffer, "id", realName);
342         return idScript;
343     }
344 
345     /**
346      * This method will write append an attribute value to a InternalStringBuilder.
347      * The method assumes that the attr is not <code>null</code>.  If the
348      * value is <code>null</code> the attribute will not be appended to the
349      * <code>InternalStringBuilder</code>.
350      */
351     private void renderAttribute(InternalStringBuilder buf, String   name, String   value)
352     {
353         assert (name != null);
354         if (value == null)
355             return;
356 
357         buf.append(" ");
358         buf.append(name);
359         buf.append("=\"");
360         buf.append(value);
361         buf.append("\"");
362     }
363 
364     private String   mapLegacyTagId(String   tagId, String   value)
365     {
366         // @todo: this is sort of broken, it needs to be updated
367         IScriptReporter scriptReporter = getScriptReporter();
368         ScriptRequestState srs = ScriptRequestState.getScriptRequestState((HttpServletRequest  ) pageContext.getRequest());
369         String   scriptId = srs.mapLegacyTagId(scriptReporter,tagId, value);
370         return scriptId;
371     }
372 }
373
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