1 /*
2 * $Id: NestedRootTag.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 package org.apache.struts.taglib.nested;
22
23 import org.apache.struts.taglib.TagUtils;
24
25 import javax.servlet.http.HttpServletRequest;
26 import javax.servlet.jsp.JspException;
27 import javax.servlet.jsp.tagext.BodyTagSupport;
28
29 /**
30 * NestedRootTag.
31 *
32 * The only other addition in this nested suite of tags. This tag allows for a
33 * nested structure to start without relying on the bean and workings of the
34 * FormTag. Useful for view pages that don't update when returning to the
35 * server, or use hyperlinks rather than form submits.
36 *
37 * The Bean that it uses can come out of a jsp:useBean tag or define another
38 * bean that's already in scope. As long as the other Struts tags can find the
39 * bean by name, it'll work.
40 *
41 * It's simply recognised by the helper class and it's property is added to
42 * the nesting list.
43 *
44 * @version $Rev: 471754 $ $Date: 2004-10-16 12:38:42 -0400 (Sat, 16 Oct 2004)
45 * $
46 * @since Struts 1.1
47 */
48 public class NestedRootTag extends BodyTagSupport implements NestedNameSupport {
49 /* usual member variables */
50 private String name = null;
51 private String originalName = "";
52 private String originalNesting = "";
53 private String originalNestingName = "";
54
55 /**
56 * Getter method for the <i>property</i> property
57 *
58 * @return String value of the property property
59 */
60 public String getProperty() {
61 return "";
62 }
63
64 /**
65 * Setter method for the <i>property</i> property
66 *
67 * @param property new value for the property property
68 */
69 public void setProperty(String property) {
70 }
71
72 /**
73 * Getter method for the <i>name</i> property
74 *
75 * @return String value of the name property
76 */
77 public String getName() {
78 return this.name;
79 }
80
81 /**
82 * Setter method for the <i>name</i> property
83 *
84 * @param name new value for the name property
85 */
86 public void setName(String name) {
87 this.name = name;
88 }
89
90 /**
91 * Overriding method of the heart of the tag. Gets the relative property
92 * and tells the JSP engine to evaluate its body content.
93 *
94 * @return int JSP continuation directive.
95 */
96 public int doStartTag() throws JspException {
97 /* set the nested reference for possible inclusions etc */
98 HttpServletRequest request =
99 (HttpServletRequest) pageContext.getRequest();
100
101 // get al the originals
102 originalName = name;
103 originalNesting = NestedPropertyHelper.getCurrentProperty(request);
104 originalNestingName =
105 NestedPropertyHelper.getCurrentName(request, this);
106
107 // set what we have to
108 if (name != null) {
109 NestedPropertyHelper.setProperty(request, "");
110 NestedPropertyHelper.setName(request, this.name);
111 }
112
113 // do the JSP thing
114 return (EVAL_BODY_TAG);
115 }
116
117 /**
118 * Render the resulting content evaluation.
119 *
120 * @return int JSP continuation directive.
121 */
122 public int doAfterBody() throws JspException {
123 /* Render the output */
124 if (bodyContent != null) {
125 TagUtils.getInstance().writePrevious(pageContext,
126 bodyContent.getString());
127 bodyContent.clearBody();
128 }
129
130 return (SKIP_BODY);
131 }
132
133 /**
134 * Evaluate the rest of the page
135 *
136 * @return int JSP continuation directive.
137 */
138 public int doEndTag() throws JspException {
139 /* reset the reference */
140 HttpServletRequest request =
141 (HttpServletRequest) pageContext.getRequest();
142
143 if (originalNesting == null) {
144 NestedPropertyHelper.deleteReference(request);
145 } else {
146 NestedPropertyHelper.setName(request, originalNestingName);
147 NestedPropertyHelper.setProperty(request, originalNesting);
148 }
149
150 this.name = originalName;
151
152 return (EVAL_PAGE);
153 }
154
155 /**
156 * JSP method to release all resources held by the tag.
157 */
158 public void release() {
159 super.release();
160 this.name = null;
161 this.originalName = null;
162 this.originalNesting = null;
163 this.originalNestingName = null;
164 }
165 }