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1   /*
2    * $Id: AddTag.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.tiles.taglib;
24  
25  import javax.servlet.jsp.JspException;
26  
27    /**
28     * Add an element to the surrounding list tag.
29     * Same syntax as <code>&lt;put&gt;</code>.
30     */
31  public class AddTag extends PutTag {
32  
33    /**
34     * default constructor
35     */
36    public AddTag() {
37      super();
38    }
39  
40      /**
41       * Call parent tag which must implement AttributeContainer.
42       * @throws JspException If we can't find an appropriate enclosing tag.
43       */
44    protected void callParent() throws JspException
45      {
46              // Get enclosing parent
47      AddTagParent enclosingParent = findEnclosingPutListTagParent();
48      enclosingParent.processNestedTag( this );
49      }
50  
51      /**
52       * Find parent tag which must implement AttributeContainer.
53       * @throws JspException If we can't find an appropriate enclosing tag.
54       */
55    protected AddTagParent findEnclosingPutListTagParent() throws JspException {
56      try
57        {
58        AddTagParent parent = (AddTagParent)findAncestorWithClass(this,AddTagParent.class);
59        if( parent == null )
60          {
61          throw new JspException( "Error - tag add : enclosing tag doesn't accept 'add' tag." );
62          }
63        return parent;
64        }
65       catch( ClassCastException ex )
66        {
67        throw new JspException( "Error - tag add : enclosing tag doesn't accept 'add' tag." , ex);
68        }
69    }
70  }