001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.xbean.kernel.standard; 018 019 import java.util.Collections; 020 import java.util.Iterator; 021 import java.util.Set; 022 023 import java.util.concurrent.locks.Lock; 024 import org.apache.xbean.kernel.Kernel; 025 import org.apache.xbean.kernel.ServiceCondition; 026 import org.apache.xbean.kernel.ServiceFactory; 027 import org.apache.xbean.kernel.ServiceName; 028 029 /** 030 * A special sub-class of AggregateCondition used to manage the stop conditions of a non-restartable service. This class 031 * will update stop conditions to reflect the stop conditions currently registered with the service factory, when the 032 * initialized or getUnsatisfied methods are called. 033 * 034 * @author Dain Sundstrom 035 * @version $Id$ 036 * @since 2.0 037 */ 038 public class NonRestartableStopCondition extends AggregateCondition { 039 private final ServiceFactory serviceFactory; 040 041 /** 042 * Creates a NonRestartableStopCondition. 043 * 044 * @param kernel the kernel in which the service is registered 045 * @param serviceName the name of the service 046 * @param classLoader the class loader for the service 047 * @param lock the lock for the service manager 048 * @param serviceFactory the service factory for the service 049 */ 050 public NonRestartableStopCondition(Kernel kernel, ServiceName serviceName, ClassLoader classLoader, Lock lock, ServiceFactory serviceFactory) { 051 super(kernel, serviceName, classLoader, lock, Collections.EMPTY_SET); 052 this.serviceFactory = serviceFactory; 053 } 054 055 /** 056 * Throws UnsupportedOperationException. Initialize is not a valid operation for a NonRestartableStopCondition 057 * 058 * @throws UnsupportedOperationException always 059 */ 060 public synchronized void initialize() throws UnsupportedOperationException { 061 throw new UnsupportedOperationException("initialize should never be called on a NonRestartableStopCondition"); 062 } 063 064 /** 065 * {@inheritDoc} 066 */ 067 public synchronized Set getUnsatisfied() { 068 updateConditions(); 069 return super.getUnsatisfied(); 070 } 071 072 private void updateConditions() { 073 if (isDestroyed()) throw new IllegalStateException("destroyed"); 074 075 Set conditions = getConditions(); 076 077 // add the new conditions 078 Set stopConditions = serviceFactory.getStopConditions(); 079 for (Iterator iterator = stopConditions.iterator(); iterator.hasNext();) { 080 ServiceCondition condition = (ServiceCondition) iterator.next(); 081 if (!conditions.contains(condition)) { 082 addCondition(condition); 083 } 084 } 085 086 // remove the conditions that were dropped 087 for (Iterator iterator = conditions.iterator(); iterator.hasNext();) { 088 ServiceCondition serviceCondition = (ServiceCondition) iterator.next(); 089 if (!stopConditions.contains(serviceCondition)) { 090 removeCondition(serviceCondition); 091 } 092 } 093 } 094 095 }