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   package javax.faces.component;
   17   
   18   import java.io.Serializable;
   19   import java.util.AbstractList;
   20   import java.util.ArrayList;
   21   import java.util.List;
   22   
   23   /**
   24    * @author Manfred Geiler (latest modification by $Author: bdudney $)
   25    * @version $Revision: 225333 $ $Date: 2005-07-26 11:49:19 -0400 (Tue, 26 Jul 2005) $
   26    */
   27   class _ComponentChildrenList
   28           extends AbstractList
   29           implements Serializable
   30   {
   31   	private static final long serialVersionUID = -6775078929331154224L;
   32   	private UIComponent _component;
   33       private List _list = new ArrayList();
   34   
   35       _ComponentChildrenList(UIComponent component)
   36       {
   37           _component = component;
   38       }
   39   
   40       public Object get(int index)
   41       {
   42           return _list.get(index);
   43       }
   44   
   45       public int size()
   46       {
   47           return _list.size();
   48       }
   49   
   50       public Object set(int index, Object value)
   51       {
   52           checkValue(value);
   53           setNewParent((UIComponent)value);
   54           UIComponent child = (UIComponent) _list.set(index, value);
   55           if (child != null) child.setParent(null);
   56           return child;
   57       }
   58   
   59       public boolean add(Object value)
   60       {
   61           checkValue(value);
   62           setNewParent((UIComponent)value);
   63           return _list.add(value);
   64       }
   65   
   66       public void add(int index, Object value)
   67       {
   68           checkValue(value);
   69           setNewParent((UIComponent)value);
   70           _list.add(index, value);
   71       }
   72   
   73       public Object remove(int index)
   74       {
   75           UIComponent child = (UIComponent) _list.remove(index);
   76           if (child != null) child.setParent(null);
   77           return child;
   78       }
   79   
   80   
   81       private void setNewParent(UIComponent child)
   82       {
   83           UIComponent oldParent = child.getParent();
   84           if (oldParent != null)
   85           {
   86               oldParent.getChildren().remove(child);
   87           }
   88           child.setParent(_component);
   89       }
   90   
   91       private void checkValue(Object value)
   92       {
   93           if (value == null) throw new NullPointerException("value");
   94           if (!(value instanceof UIComponent)) throw new ClassCastException("value is not a UIComponent");
   95       }
   96   
   97   }