001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     * 
010     *      http://www.apache.org/licenses/LICENSE-2.0
011     * 
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    package org.apache.oozie.service;
019    
020    import org.apache.hadoop.util.ReflectionUtils;
021    import org.apache.oozie.action.ActionExecutor;
022    import org.apache.oozie.action.control.EndActionExecutor;
023    import org.apache.oozie.action.control.ForkActionExecutor;
024    import org.apache.oozie.action.control.JoinActionExecutor;
025    import org.apache.oozie.action.control.KillActionExecutor;
026    import org.apache.oozie.action.control.StartActionExecutor;
027    import org.apache.oozie.service.Service;
028    import org.apache.oozie.service.ServiceException;
029    import org.apache.oozie.service.Services;
030    import org.apache.oozie.util.ParamChecker;
031    import org.apache.oozie.util.XLog;
032    import org.apache.oozie.ErrorCode;
033    
034    import java.util.HashMap;
035    import java.util.Map;
036    
037    public class ActionService implements Service {
038    
039        public static final String CONF_ACTION_EXECUTOR_CLASSES = CONF_PREFIX + "ActionService.executor.classes";
040    
041        public static final String CONF_ACTION_EXECUTOR_EXT_CLASSES = CONF_PREFIX + "ActionService.executor.ext.classes";
042    
043        private Services services;
044        private Map<String, Class<? extends ActionExecutor>> executors;
045    
046        @SuppressWarnings("unchecked")
047        public void init(Services services) throws ServiceException {
048            this.services = services;
049            ActionExecutor.enableInit();
050            ActionExecutor.resetInitInfo();
051            ActionExecutor.disableInit();
052            executors = new HashMap<String, Class<? extends ActionExecutor>>();
053    
054            Class<? extends ActionExecutor>[] classes = new Class[] { StartActionExecutor.class,
055                EndActionExecutor.class, KillActionExecutor.class,  ForkActionExecutor.class, JoinActionExecutor.class };
056            registerExecutors(classes);
057    
058            classes = (Class<? extends ActionExecutor>[]) services.getConf().getClasses(CONF_ACTION_EXECUTOR_CLASSES);
059            registerExecutors(classes);
060    
061            classes = (Class<? extends ActionExecutor>[]) services.getConf().getClasses(CONF_ACTION_EXECUTOR_EXT_CLASSES);
062            registerExecutors(classes);
063        }
064    
065        private void registerExecutors(Class<? extends ActionExecutor>[] classes) throws ServiceException {
066            if (classes != null) {
067                for (Class<? extends ActionExecutor> executorClass : classes) {
068                    register(executorClass);
069                }
070            }
071        }
072    
073        public void destroy() {
074            ActionExecutor.enableInit();
075            ActionExecutor.resetInitInfo();
076            ActionExecutor.disableInit();
077            executors = null;
078        }
079    
080        public Class<? extends Service> getInterface() {
081            return ActionService.class;
082        }
083    
084        public void register(Class<? extends ActionExecutor> klass) throws ServiceException {
085            XLog log = XLog.getLog(getClass());
086            ActionExecutor executor = (ActionExecutor) ReflectionUtils.newInstance(klass, services.getConf());
087            log.trace("Registering action type [{0}] class [{1}]", executor.getType(), klass);
088            if (executors.containsKey(executor.getType())) {
089                throw new ServiceException(ErrorCode.E0150, executor.getType());
090            }
091            ActionExecutor.enableInit();
092            executor.initActionType();
093            ActionExecutor.disableInit();
094            executors.put(executor.getType(), klass);
095            log.trace("Registered Action executor for action type [{0}] class [{1}]", executor.getType(), klass);
096        }
097    
098        public ActionExecutor getExecutor(String actionType) {
099            ParamChecker.notEmpty(actionType, "actionType");
100            Class<? extends ActionExecutor> executorClass = executors.get(actionType);
101            return (executorClass != null) ? (ActionExecutor) ReflectionUtils.newInstance(executorClass, null) : null;
102        }
103    
104    }