001// Copyright 2006, 2007, 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.services; 016 017import org.apache.tapestry5.func.F; 018import org.apache.tapestry5.func.Worker; 019import org.apache.tapestry5.ioc.internal.util.OneShotLock; 020import org.apache.tapestry5.ioc.services.RegistryShutdownHub; 021import org.apache.tapestry5.ioc.services.RegistryShutdownListener; 022import org.slf4j.Logger; 023 024import java.util.List; 025 026import static org.apache.tapestry5.ioc.internal.util.CollectionFactory.newThreadSafeList; 027 028public class RegistryShutdownHubImpl implements RegistryShutdownHub 029{ 030 private final OneShotLock lock = new OneShotLock(); 031 032 private final Logger logger; 033 034 private final List<Runnable> listeners = newThreadSafeList(); 035 036 private final List<Runnable> preListeners = newThreadSafeList(); 037 038 public RegistryShutdownHubImpl(Logger logger) 039 { 040 this.logger = logger; 041 } 042 043 public void addRegistryShutdownListener(final RegistryShutdownListener listener) 044 { 045 assert listener != null; 046 047 addRegistryShutdownListener(new Runnable() 048 { 049 public void run() 050 { 051 listener.registryDidShutdown(); 052 } 053 }); 054 } 055 056 public void addRegistryShutdownListener(Runnable listener) 057 { 058 assert listener != null; 059 060 lock.check(); 061 062 listeners.add(listener); 063 } 064 065 public void addRegistryWillShutdownListener(Runnable listener) 066 { 067 assert listener != null; 068 069 lock.check(); 070 071 preListeners.add(listener); 072 } 073 074 /** 075 * Fires the {@link RegistryShutdownListener#registryDidShutdown()} method on each listener. At the end, all the 076 * listeners are discarded. 077 */ 078 public void fireRegistryDidShutdown() 079 { 080 lock.lock(); 081 082 F.flow(preListeners).concat(listeners).each(new Worker<Runnable>() 083 { 084 public void work(Runnable element) 085 { 086 try 087 { 088 element.run(); 089 } catch (RuntimeException ex) 090 { 091 logger.error(ServiceMessages.shutdownListenerError(element, ex), ex); 092 } 093 } 094 }); 095 096 preListeners.clear(); 097 listeners.clear(); 098 } 099 100}