001// Copyright 2010, 2011, 2012 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;
016
017import org.apache.tapestry5.commons.ObjectCreator;
018import org.apache.tapestry5.commons.services.PlasticProxyFactory;
019import org.apache.tapestry5.ioc.ServiceBuilderResources;
020import org.apache.tapestry5.ioc.services.UpdateListenerHub;
021
022import java.lang.reflect.Method;
023
024/**
025 * Responsible for creating a {@link ReloadableServiceImplementationObjectCreator} for a service implementation.
026 */
027@SuppressWarnings("unchecked")
028public class ReloadableObjectCreatorSource implements ObjectCreatorSource
029{
030    private final PlasticProxyFactory proxyFactory;
031
032    private final Method bindMethod;
033
034    private final Class serviceInterfaceClass;
035
036    private final Class serviceImplementationClass;
037
038    private final boolean eagerLoad;
039
040    public ReloadableObjectCreatorSource(PlasticProxyFactory proxyFactory, Method bindMethod,
041                                         Class serviceInterfaceClass, Class serviceImplementationClass, boolean eagerLoad)
042    {
043        this.proxyFactory = proxyFactory;
044        this.bindMethod = bindMethod;
045        this.serviceInterfaceClass = serviceInterfaceClass;
046        this.serviceImplementationClass = serviceImplementationClass;
047        this.eagerLoad = eagerLoad;
048    }
049
050
051    @Override
052    public ObjectCreator constructCreator(final ServiceBuilderResources resources)
053    {
054        return new ObjectCreator()
055        {
056            @Override
057            public Object createObject()
058            {
059                return createReloadableProxy(resources);
060            }
061
062            @Override
063            public String toString()
064            {
065                return proxyFactory.getMethodLocation(bindMethod).toString();
066            }
067        };
068    }
069
070    @Override
071    public String getDescription()
072    {
073        return String.format("Reloadable %s via %s", serviceImplementationClass.getName(),
074                proxyFactory.getMethodLocation(bindMethod));
075    }
076
077    private Object createReloadableProxy(ServiceBuilderResources resources)
078    {
079        ReloadableServiceImplementationObjectCreator reloadableCreator = new ReloadableServiceImplementationObjectCreator(proxyFactory,
080                resources, proxyFactory.getClassLoader(), serviceImplementationClass.getName());
081
082        resources.getService(UpdateListenerHub.class).addUpdateListener(reloadableCreator);
083
084        if (eagerLoad)
085        {
086            reloadableCreator.createObject();
087        }
088
089        return proxyFactory.createProxy(serviceInterfaceClass, resources.getServiceImplementation(), reloadableCreator, getDescription());
090    }
091}