001// Copyright 2006-2013 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.func.F;
018import org.apache.tapestry5.func.Predicate;
019import org.apache.tapestry5.ioc.ObjectLocator;
020import org.apache.tapestry5.ioc.OperationTracker;
021import org.apache.tapestry5.ioc.annotations.Inject;
022import org.apache.tapestry5.ioc.util.ExceptionUtils;
023import org.apache.tapestry5.model.MutableComponentModel;
024import org.apache.tapestry5.plastic.PlasticClass;
025import org.apache.tapestry5.plastic.PlasticField;
026import org.apache.tapestry5.services.transform.ComponentClassTransformWorker2;
027import org.apache.tapestry5.services.transform.InjectionProvider2;
028import org.apache.tapestry5.services.transform.TransformationSupport;
029
030/**
031 * Performs injection triggered by any field annotated with the {@link org.apache.tapestry5.ioc.annotations.Inject}
032 * annotation or the {@link javax.inject.Inject} annotation.
033 * <p/>
034 * The implementation of this worker mostly delegates to a chain of command of {@link InjectionProvider2}.
035 */
036public class InjectWorker implements ComponentClassTransformWorker2
037{
038    private final ObjectLocator locator;
039
040    // Really, a chain of command
041
042    private final InjectionProvider2 injectionProvider;
043
044    private final OperationTracker tracker;
045
046    private final Predicate<PlasticField> MATCHER = new Predicate<PlasticField>()
047    {
048        public boolean accept(PlasticField field)
049        {
050            return field.hasAnnotation(Inject.class) ||
051                    field.hasAnnotation(javax.inject.Inject.class);
052        }
053    };
054
055    public InjectWorker(ObjectLocator locator, InjectionProvider2 injectionProvider, OperationTracker tracker)
056    {
057        this.locator = locator;
058        this.injectionProvider = injectionProvider;
059        this.tracker = tracker;
060    }
061
062    public void transform(final PlasticClass plasticClass, TransformationSupport support, final MutableComponentModel model)
063    {
064        for (final PlasticField field : F.flow(plasticClass.getUnclaimedFields()).filter(MATCHER))
065        {
066            final String fieldName = field.getName();
067
068            tracker.run(String.format("Injecting field  %s.%s", plasticClass.getClassName(), fieldName), new Runnable()
069            {
070                public void run()
071                {
072                    try
073                    {
074                        boolean success = injectionProvider.provideInjection(field, locator, model);
075
076                        if (success)
077                        {
078                            field.claim("@Inject");
079                        }
080                    } catch (RuntimeException ex)
081                    {
082                        throw new RuntimeException(String.format("Error obtaining injected value for field %s.%s: %s", plasticClass.getClassName(), fieldName, ExceptionUtils.toMessage(ex)), ex);
083                    }
084                }
085            });
086        }
087    }
088}