001// Copyright 2007, 2008, 2010 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.tapestry5.internal.services;
016
017import org.apache.tapestry5.ComponentResources;
018import org.apache.tapestry5.internal.structure.Page;
019import org.apache.tapestry5.runtime.Component;
020import org.apache.tapestry5.runtime.RenderCommand;
021import org.apache.tapestry5.services.Ajax;
022import org.apache.tapestry5.services.ComponentEventResultProcessor;
023
024import java.io.IOException;
025
026/**
027 * Performs a partial page render based on a root component. If the component is actually a page,
028 * it will send an JSON reponse to rediret to the page.
029 */
030@SuppressWarnings("all")
031public class AjaxComponentInstanceEventResultProcessor implements ComponentEventResultProcessor<Component>
032{
033    private final RequestPageCache cache;
034
035    private final ComponentEventResultProcessor masterProcessor;
036
037    public AjaxComponentInstanceEventResultProcessor(RequestPageCache cache, @Ajax
038    ComponentEventResultProcessor masterProcessor)
039    {
040        this.cache = cache;
041        this.masterProcessor = masterProcessor;
042    }
043
044    public void processResultValue(Component value) throws IOException
045    {
046        ComponentResources resources = value.getComponentResources();
047
048        boolean isPage = value == resources.getPage();
049
050        String pageName = resources.getPageName();
051
052        if (isPage)
053        {
054            // This will ultimately send a JSON response to redirect to the page
055
056            masterProcessor.processResultValue(pageName);
057            return;
058        }
059
060        // Otherwise, a component within a page. Components are transformed to implement RenderCommand, but if we just
061        // pass the component itself to the master processor, we'll get in a loop, so we instead
062        // pass the ComponentPageElement (which implements RenderCommand as well).
063
064        Page page = cache.get(pageName);
065
066        String nestedId = resources.getNestedId();
067
068        RenderCommand command = page.getComponentElementByNestedId(nestedId);
069
070        masterProcessor.processResultValue(command);
071    }
072}