    001// Copyright 2007, 2008, 2010, 2011 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.transform;
    016
    017import org.apache.tapestry5.MarkupWriter;
    018import org.apache.tapestry5.internal.InternalComponentResources;
    019import org.apache.tapestry5.model.MutableComponentModel;
    020import org.apache.tapestry5.plastic.MethodDescription;
    021import org.apache.tapestry5.plastic.PlasticClass;
    022import org.apache.tapestry5.plastic.PlasticField;
    023import org.apache.tapestry5.plastic.PlasticUtils;
    024import org.apache.tapestry5.runtime.RenderCommand;
    025import org.apache.tapestry5.runtime.RenderQueue;
    026import org.apache.tapestry5.services.TransformConstants;
    027import org.apache.tapestry5.services.transform.ComponentClassTransformWorker2;
    028import org.apache.tapestry5.services.transform.TransformationSupport;
    029
    030/**
    031 * Ensures that all components implement {@link RenderCommand} by delegating to
    032 * {@link InternalComponentResources#render(org.apache.tapestry5.MarkupWriter, org.apache.tapestry5.runtime.RenderQueue)}.
    033 * This is also responsible for invoking {@link org.apache.tapestry5.internal.InternalComponentResources#postRenderCleanup()}
    034 */
    035public class RenderCommandWorker implements ComponentClassTransformWorker2
    036{
    037
    038    private final MethodDescription RENDER_DESCRIPTION = PlasticUtils.getMethodDescription(RenderCommand.class, "render", MarkupWriter.class, RenderQueue.class);
    039
    040    public void transform(PlasticClass plasticClass, TransformationSupport support, MutableComponentModel model)
    041    {
    042        // Subclasses don't need to bother, they'll inherit from super-classes.
    043
    044        if (!support.isRootTransformation())
    045        {
    046            return;
    047        }
    048
    049        plasticClass.introduceInterface(RenderCommand.class);
    050
    051        PlasticField resourcesField = plasticClass.introduceField(InternalComponentResources.class, "resources").injectFromInstanceContext();
    052
    053        plasticClass.introduceMethod(RENDER_DESCRIPTION).delegateTo(resourcesField);
    054
    055        plasticClass.introduceMethod(TransformConstants.POST_RENDER_CLEANUP_DESCRIPTION).delegateTo(resourcesField);
    056    }
    057}