    001// Copyright 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.ioc.internal.util;
    016
    017import org.apache.tapestry5.ioc.Invokable;
    018import org.apache.tapestry5.ioc.ObjectCreator;
    019import org.apache.tapestry5.ioc.OperationTracker;
    020
    021import java.util.List;
    022
    023/**
    024 * Encapsulates the initial construction of an object instance, followed by a series
    025 * {@link InitializationPlan}s to initialize fields and invoke other methods of the constructed object.
    026 *
    027 * @since 5.3
    028 */
    029public class ConstructionPlan<T> implements ObjectCreator<T>
    030{
    031    private final OperationTracker tracker;
    032
    033    private final String description;
    034
    035    private final Invokable<T> instanceConstructor;
    036
    037    private List<InitializationPlan> initializationPlans;
    038
    039    public ConstructionPlan(OperationTracker tracker, String description, Invokable<T> instanceConstructor)
    040    {
    041        this.tracker = tracker;
    042        this.description = description;
    043        this.instanceConstructor = instanceConstructor;
    044    }
    045
    046    public ConstructionPlan add(InitializationPlan plan)
    047    {
    048        if (initializationPlans == null)
    049        {
    050            initializationPlans = CollectionFactory.newList();
    051        }
    052
    053        initializationPlans.add(plan);
    054
    055        return this;
    056    }
    057
    058    @Override
    059    public T createObject()
    060    {
    061        T result = tracker.invoke(description, instanceConstructor);
    062
    063        if (initializationPlans != null)
    064        {
    065            executeInitializationPLans(result);
    066        }
    067
    068        return result;
    069    }
    070
    071    private void executeInitializationPLans(final T newInstance)
    072    {
    073        for (final InitializationPlan<T> plan : initializationPlans)
    074        {
    075            tracker.run(plan.getDescription(), new Runnable()
    076            {
    077                @Override
    078                public void run()
    079                {
    080                    plan.initialize(newInstance);
    081                }
    082            });
    083        }
    084    }
    085}