    001// Copyright 2006, 2007, 2008, 2010, 2011, 2023 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.annotations.InjectPage;
    018import org.apache.tapestry5.commons.ObjectCreator;
    019import org.apache.tapestry5.internal.services.ComponentDependencyRegistry;
    020import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    021import org.apache.tapestry5.ioc.services.PerthreadManager;
    022import org.apache.tapestry5.model.MutableComponentModel;
    023import org.apache.tapestry5.plastic.InstanceContext;
    024import org.apache.tapestry5.plastic.PlasticClass;
    025import org.apache.tapestry5.plastic.PlasticField;
    026import org.apache.tapestry5.services.ComponentClassResolver;
    027import org.apache.tapestry5.services.ComponentSource;
    028import org.apache.tapestry5.services.transform.ComponentClassTransformWorker2;
    029import org.apache.tapestry5.services.transform.TransformationSupport;
    030
    031/**
    032 * Performs transformations that allow pages to be injected into components.
    033 *
    034 * @see org.apache.tapestry5.annotations.InjectPage
    035 */
    036public class InjectPageWorker implements ComponentClassTransformWorker2
    037{
    038    private final class InjectedPageConduit extends ReadOnlyComponentFieldConduit
    039    {
    040        private final String injectedPageName;
    041
    042        private final ObjectCreator<Object> pageValue = perThreadManager.createValue(new ObjectCreator<Object>() {
    043            @Override
    044            public Object createObject() {
    045                return componentSource.getPage(injectedPageName);
    046            }
    047        });
    048
    049        private InjectedPageConduit(String className, String fieldName,
    050                                    String injectedPageName)
    051        {
    052            super(className, fieldName);
    053
    054            this.injectedPageName = injectedPageName;
    055        }
    056
    057        public Object get(Object instance, InstanceContext context)
    058        {
    059            return pageValue.createObject();
    060        }
    061    }
    062
    063    private final ComponentSource componentSource;
    064
    065    private final ComponentClassResolver resolver;
    066
    067    private final PerthreadManager perThreadManager;
    068
    069    private final ComponentDependencyRegistry componentDependencyRegistry;
    070
    071    public InjectPageWorker(ComponentSource componentSource, ComponentClassResolver resolver, PerthreadManager perThreadManager,
    072            ComponentDependencyRegistry componentDependencyRegistry)
    073    {
    074        this.componentSource = componentSource;
    075        this.resolver = resolver;
    076        this.perThreadManager = perThreadManager;
    077        this.componentDependencyRegistry = componentDependencyRegistry;
    078    }
    079
    080    public void transform(PlasticClass plasticClass, TransformationSupport support, MutableComponentModel model)
    081    {
    082        for (PlasticField field : plasticClass.getFieldsWithAnnotation(InjectPage.class))
    083        {
    084            addInjectedPage(field, model);
    085        }
    086    }
    087
    088    private void addInjectedPage(PlasticField field, MutableComponentModel model)
    089    {
    090        InjectPage annotation = field.getAnnotation(InjectPage.class);
    091
    092        field.claim(annotation);
    093
    094        String pageName = annotation.value();
    095
    096        String fieldName = field.getName();
    097
    098        String injectedPageName = InternalUtils.isBlank(pageName) ? resolver
    099                .resolvePageClassNameToPageName(field.getTypeName()) : pageName;
    100
    101        field.setConduit(new InjectedPageConduit(field.getPlasticClass().getClassName(), fieldName, injectedPageName));
    102
    103        componentDependencyRegistry.register(field, model);
    104    }
    105}