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 */
018package org.apache.oozie.service;
019
020import org.apache.hadoop.util.ReflectionUtils;
021import org.apache.oozie.action.ActionExecutor;
022import org.apache.oozie.action.control.EndActionExecutor;
023import org.apache.oozie.action.control.ForkActionExecutor;
024import org.apache.oozie.action.control.JoinActionExecutor;
025import org.apache.oozie.action.control.KillActionExecutor;
026import org.apache.oozie.action.control.StartActionExecutor;
027import org.apache.oozie.service.Service;
028import org.apache.oozie.service.ServiceException;
029import org.apache.oozie.service.Services;
030import org.apache.oozie.util.ParamChecker;
031import org.apache.oozie.util.XLog;
032import org.apache.oozie.ErrorCode;
033
034import java.util.HashMap;
035import java.util.Map;
036
037public 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}