001// Copyright 2004, 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry.pageload;
016
017import java.util.Collection;
018import java.util.Iterator;
019
020import org.apache.tapestry.IComponent;
021import org.apache.tapestry.Tapestry;
022
023/**
024 *  Walks through the tree of components and invokes the visitors on each of 
025 *  of the components in the tree.
026 * 
027 *  @author mindbridge
028 *  @since 3.0
029 */
030public class ComponentTreeWalker
031{
032    private IComponentVisitor[] _visitors;
033    
034    public ComponentTreeWalker(IComponentVisitor[] visitors)
035    {
036        _visitors = visitors;
037    }
038
039    public void walkComponentTree(IComponent component)
040    {
041        // Invoke visitors
042        for (int i = 0; i < _visitors.length; i++)
043        {
044            IComponentVisitor visitor = _visitors[i];
045            visitor.visitComponent(component);
046        }
047
048        // Recurse into the embedded components
049        Collection components = component.getComponents().values();
050
051        if (Tapestry.size(components) == 0)
052            return;
053
054        for (Iterator it = components.iterator(); it.hasNext();)
055        {
056            IComponent embedded = (IComponent) it.next();
057            walkComponentTree(embedded);
058        }
059    }
060}