| /* |
| * $Id$ |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.tiles.request.render; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.apache.tiles.request.Request; |
| |
| /** |
| * Renders an attribute that has no associated renderer using delegation to |
| * other renderers. |
| * |
| * @version $Rev$ $Date$ |
| */ |
| public class ChainedDelegateRenderer implements Renderer { |
| |
| /** |
| * The list of chained renderers. |
| */ |
| private List<Renderer> renderers; |
| |
| /** |
| * Constructor. |
| */ |
| public ChainedDelegateRenderer() { |
| renderers = new ArrayList<Renderer>(); |
| } |
| |
| /** |
| * Adds an attribute renderer to the list. The first inserted this way, the |
| * first is checked when rendering. |
| * |
| * @param renderer The renderer to add. |
| */ |
| public void addAttributeRenderer(Renderer renderer) { |
| renderers.add(renderer); |
| } |
| |
| |
| @Override |
| public void render(String value, Request request) throws IOException { |
| if (value == null) { |
| throw new NullPointerException("The attribute value is null"); |
| } |
| |
| for (Renderer renderer : renderers) { |
| if (renderer.isRenderable(value, request)) { |
| renderer.render(value, request); |
| return; |
| } |
| } |
| |
| throw new CannotRenderException("Cannot renderer value '" + value + "'"); |
| } |
| |
| /** {@inheritDoc} */ |
| public boolean isRenderable(String value, Request request) { |
| for (Renderer renderer : renderers) { |
| if (renderer.isRenderable(value, request)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| } |