    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.commons.ObjectCreator;
    018import org.apache.tapestry5.commons.util.CollectionFactory;
    019import org.apache.tapestry5.ioc.Invokable;
    020import org.apache.tapestry5.ioc.OperationTracker;
    021
    022import java.util.List;
    023
    024/**
    025 * Encapsulates the initial construction of an object instance, followed by a series
    026 * {@link InitializationPlan}s to initialize fields and invoke other methods of the constructed object.
    027 *
    028 * @since 5.3
    029 */
    030public class ConstructionPlan<T> implements ObjectCreator<T>
    031{
    032    private final OperationTracker tracker;
    033
    034    private final String description;
    035
    036    private final Invokable<T> instanceConstructor;
    037
    038    private List<InitializationPlan> initializationPlans;
    039
    040    public ConstructionPlan(OperationTracker tracker, String description, Invokable<T> instanceConstructor)
    041    {
    042        this.tracker = tracker;
    043        this.description = description;
    044        this.instanceConstructor = instanceConstructor;
    045    }
    046
    047    public ConstructionPlan add(InitializationPlan plan)
    048    {
    049        if (initializationPlans == null)
    050        {
    051            initializationPlans = CollectionFactory.newList();
    052        }
    053
    054        initializationPlans.add(plan);
    055
    056        return this;
    057    }
    058
    059    @Override
    060    public T createObject()
    061    {
    062        T result = tracker.invoke(description, instanceConstructor);
    063
    064        if (initializationPlans != null)
    065        {
    066            executeInitializationPLans(result);
    067        }
    068
    069        return result;
    070    }
    071
    072    private void executeInitializationPLans(final T newInstance)
    073    {
    074        for (final InitializationPlan<T> plan : initializationPlans)
    075        {
    076            tracker.run(plan.getDescription(), new Runnable()
    077            {
    078                @Override
    079                public void run()
    080                {
    081                    plan.initialize(newInstance);
    082                }
    083            });
    084        }
    085    }
    086}