| 1 | /* |
| 2 | * Copyright 2006-2007 the original author or authors. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package org.springframework.batch.core.configuration.support; |
| 18 | |
| 19 | import java.util.ArrayList; |
| 20 | import java.util.Collection; |
| 21 | |
| 22 | import org.springframework.batch.core.Job; |
| 23 | import org.springframework.batch.core.configuration.DuplicateJobException; |
| 24 | import org.springframework.batch.core.configuration.JobRegistry; |
| 25 | import org.springframework.beans.factory.InitializingBean; |
| 26 | import org.springframework.context.ApplicationContext; |
| 27 | import org.springframework.context.ApplicationContextAware; |
| 28 | import org.springframework.context.ApplicationEvent; |
| 29 | import org.springframework.context.ApplicationListener; |
| 30 | import org.springframework.context.Lifecycle; |
| 31 | import org.springframework.context.event.ContextClosedEvent; |
| 32 | import org.springframework.context.event.ContextRefreshedEvent; |
| 33 | import org.springframework.core.Ordered; |
| 34 | import org.springframework.util.Assert; |
| 35 | |
| 36 | /** |
| 37 | * Loads and unloads {@link Job Jobs} when the application context is created and destroyed. Each resource provided is |
| 38 | * loaded as an application context with the current context as its parent, and then all the jobs from the child context |
| 39 | * are registered under their bean names. A {@link JobRegistry} is required. |
| 40 | * |
| 41 | * @author Lucas Ward |
| 42 | * @author Dave Syer |
| 43 | * |
| 44 | * @since 2.1 |
| 45 | */ |
| 46 | public class AutomaticJobRegistrar implements Ordered, Lifecycle, ApplicationListener, ApplicationContextAware, |
| 47 | InitializingBean { |
| 48 | |
| 49 | private Collection<ApplicationContextFactory> applicationContextFactories = new ArrayList<ApplicationContextFactory>(); |
| 50 | |
| 51 | private JobLoader jobLoader; |
| 52 | |
| 53 | private ApplicationContext applicationContext; |
| 54 | |
| 55 | private volatile boolean running = false; |
| 56 | |
| 57 | private Object lifecycleMonitor = new Object(); |
| 58 | |
| 59 | private int order = Ordered.LOWEST_PRECEDENCE; |
| 60 | |
| 61 | /** |
| 62 | * The enclosing application context, which can be used to check if {@link ApplicationEvent events} come from the |
| 63 | * expected source. |
| 64 | * |
| 65 | * @param applicationContext the enclosing application context if there is one |
| 66 | * @see ApplicationContextAware#setApplicationContext(ApplicationContext) |
| 67 | */ |
| 68 | @Override |
| 69 | public void setApplicationContext(ApplicationContext applicationContext) { |
| 70 | this.applicationContext = applicationContext; |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * Add some factories to the set that will be used to load contexts and jobs. |
| 75 | * |
| 76 | * @param applicationContextFactory the {@link ApplicationContextFactory} values to use |
| 77 | */ |
| 78 | public void addApplicationContextFactory(ApplicationContextFactory applicationContextFactory) { |
| 79 | if (applicationContextFactory instanceof ApplicationContextAware) { |
| 80 | ((ApplicationContextAware) applicationContextFactory).setApplicationContext(applicationContext); |
| 81 | } |
| 82 | this.applicationContextFactories.add(applicationContextFactory); |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Add some factories to the set that will be used to load contexts and jobs. |
| 87 | * |
| 88 | * @param applicationContextFactories the {@link ApplicationContextFactory} values to use |
| 89 | */ |
| 90 | public void setApplicationContextFactories(ApplicationContextFactory[] applicationContextFactories) { |
| 91 | for (ApplicationContextFactory applicationContextFactory : applicationContextFactories) { |
| 92 | this.applicationContextFactories.add(applicationContextFactory); |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | /** |
| 97 | * The job loader that will be used to load and manage jobs. |
| 98 | * |
| 99 | * @param jobLoader the {@link JobLoader} to set |
| 100 | */ |
| 101 | public void setJobLoader(JobLoader jobLoader) { |
| 102 | this.jobLoader = jobLoader; |
| 103 | } |
| 104 | |
| 105 | @Override |
| 106 | public int getOrder() { |
| 107 | return order; |
| 108 | } |
| 109 | |
| 110 | /** |
| 111 | * The order to start up and shutdown. |
| 112 | * @param order the order (default {@link Ordered#LOWEST_PRECEDENCE}). |
| 113 | * @see Ordered |
| 114 | */ |
| 115 | public void setOrder(int order) { |
| 116 | this.order = order; |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | */ |
| 121 | @Override |
| 122 | public void afterPropertiesSet() { |
| 123 | |
| 124 | Assert.state(jobLoader != null, "A JobLoader must be provided"); |
| 125 | |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * Creates all the application contexts required and set up job registry entries with all the instances of |
| 130 | * {@link Job} found therein. Also closes the contexts when the enclosing context is closed. |
| 131 | * |
| 132 | * @see InitializingBean#afterPropertiesSet() |
| 133 | */ |
| 134 | @Override |
| 135 | public final void onApplicationEvent(ApplicationEvent event) { |
| 136 | // TODO: With Spring 3 a SmartLifecycle is started automatically |
| 137 | if (event.getSource() == applicationContext) { |
| 138 | if (event instanceof ContextRefreshedEvent) { |
| 139 | start(); |
| 140 | } |
| 141 | else if (event instanceof ContextClosedEvent) { |
| 142 | stop(); |
| 143 | } |
| 144 | } |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * Delegates to {@link JobLoader#clear()}. |
| 149 | * |
| 150 | * @see Lifecycle#stop() |
| 151 | */ |
| 152 | @Override |
| 153 | public void stop() { |
| 154 | synchronized (this.lifecycleMonitor) { |
| 155 | jobLoader.clear(); |
| 156 | running = false; |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * Take all the contexts from the factories provided and pass them to the {@link JobLoader}. |
| 162 | * |
| 163 | * @see Lifecycle#start() |
| 164 | */ |
| 165 | @Override |
| 166 | public void start() { |
| 167 | synchronized (this.lifecycleMonitor) { |
| 168 | if (running) { |
| 169 | return; |
| 170 | } |
| 171 | for (ApplicationContextFactory factory : applicationContextFactories) { |
| 172 | try { |
| 173 | jobLoader.load(factory); |
| 174 | } |
| 175 | catch (DuplicateJobException e) { |
| 176 | throw new IllegalStateException(e); |
| 177 | } |
| 178 | } |
| 179 | running = true; |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | /** |
| 184 | * Check if this component has been started. |
| 185 | * |
| 186 | * @return true if started successfully and not stopped |
| 187 | * @see Lifecycle#isRunning() |
| 188 | */ |
| 189 | @Override |
| 190 | public boolean isRunning() { |
| 191 | synchronized (this.lifecycleMonitor) { |
| 192 | return running; |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | } |