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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.myfaces.custom.tree2;
20  
21  import java.util.StringTokenizer;
22  import java.util.ArrayList;
23  
24  /**
25   * Model class for the tree component.  It provides random access to nodes in a tree
26   * made up of instances of the {@link TreeNode} class.
27   *
28   * @author Sean Schofield
29   * @author Hans Bergsten (Some code taken from an example in his O'Reilly JavaServer Faces book. Copied with permission)
30   * @version $Revision: 168205 $ $Date: 2005-05-04 18:59:21 -0400 (Wed, 04 May 2005) $
31   */
32  public class TreeModelBase implements TreeModel
33  {
34  
35      private static final long serialVersionUID = 3969414475396945742L;
36  //  private static final Log log = LogFactory.getLog(TreeModelBase.class);
37  
38      private TreeNode root;
39      private TreeState treeState = new TreeStateBase();
40  
41  
42      /**
43       * Constructor
44       * @param root The root TreeNode
45       */
46      public TreeModelBase(TreeNode root)
47      {
48          this.root = root;
49      }
50  
51      // see interface
52      public TreeState getTreeState()
53      {
54          return treeState;
55      }
56  
57      // see interface
58      public void setTreeState(TreeState treeState)
59      {
60          this.treeState = treeState;
61      }
62  
63  
64  
65      /**
66       * Gets an array of String containing the ID's of all of the {@link TreeNode}s in the path to
67       * the specified node.  The path information will be an array of <code>String</code> objects
68       * representing node ID's. The array will starting with the ID of the root node and end with
69       * the ID of the specified node.
70       *
71       * @param nodeId The id of the node for whom the path information is needed.
72       * @return String[]
73       */
74      public String[] getPathInformation(String nodeId)
75      {
76          if (nodeId == null)
77          {
78              throw new IllegalArgumentException("Cannot determine parents for a null node.");
79          }
80  
81          ArrayList pathList = new ArrayList();
82          pathList.add(nodeId);
83  
84          while (nodeId.lastIndexOf(SEPARATOR) != -1)
85          {
86              nodeId = nodeId.substring(0, nodeId.lastIndexOf(SEPARATOR));
87              pathList.add(nodeId);
88          }
89  
90          String[] pathInfo = new String[pathList.size()];
91  
92          for (int i=0; i < pathInfo.length; i++)
93          {
94              pathInfo[i] = (String)pathList.get(pathInfo.length - i - 1);
95          }
96  
97          return pathInfo;
98      }
99  
100     /**
101      * Indicates whether or not the specified {@link TreeNode} is the last child in the <code>List</code>
102      * of children.  If the node id provided corresponds to the root node, this returns <code>true</code>.
103      *
104      * @param nodeId The ID of the node to check
105      * @return boolean
106      */
107     public boolean isLastChild(String nodeId)
108     {
109         if (nodeId.lastIndexOf(SEPARATOR) == -1)
110         {
111             // root node considered to be the last child
112             return true;
113         }
114 
115         //first get the id of the parent
116         String parentId = nodeId.substring(0, nodeId.lastIndexOf(SEPARATOR));
117         String childString = nodeId.substring(nodeId.lastIndexOf(SEPARATOR) + 1);
118         int childId = Integer.parseInt(childString);
119         TreeNode parentNode = getNodeById(parentId);
120 
121         return  childId + 1== parentNode.getChildCount();
122     }
123 
124     public TreeNode getNodeById(String nodeId)
125     {
126         if (nodeId == null)
127             return null;
128 
129         TreeNode node = null;
130         StringTokenizer st = new StringTokenizer(nodeId, SEPARATOR);
131 
132         while (st.hasMoreTokens())
133         {
134             int nodeIndex = Integer.parseInt(st.nextToken());
135             if(node == null)
136             {
137                 node = root;
138             }
139             else
140             {
141                 // don't worry about invalid index, that exception will be caught later and dealt with
142                 node = (TreeNode)node.getChildren().get(nodeIndex);
143             }
144         }
145 
146         return node;
147     }
148 
149     // see interface
150     public TreeWalker getTreeWalker()
151     {
152         return new TreeWalkerBase();
153     }
154 }