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;
033import java.util.HashMap;
034import java.util.Map;
035import java.util.Set;
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    private static XLog LOG = XLog.getLog(ActionService.class);
046
047    @SuppressWarnings("unchecked")
048    public void init(Services services) throws ServiceException {
049        this.services = services;
050        ActionExecutor.enableInit();
051        ActionExecutor.resetInitInfo();
052        ActionExecutor.disableInit();
053        executors = new HashMap<String, Class<? extends ActionExecutor>>();
054
055        Class<? extends ActionExecutor>[] classes = new Class[] { StartActionExecutor.class,
056            EndActionExecutor.class, KillActionExecutor.class,  ForkActionExecutor.class, JoinActionExecutor.class };
057        registerExecutors(classes);
058
059        classes = (Class<? extends ActionExecutor>[]) services.getConf().getClasses(CONF_ACTION_EXECUTOR_CLASSES);
060        registerExecutors(classes);
061
062        classes = (Class<? extends ActionExecutor>[]) services.getConf().getClasses(CONF_ACTION_EXECUTOR_EXT_CLASSES);
063        registerExecutors(classes);
064    }
065
066    private void registerExecutors(Class<? extends ActionExecutor>[] classes) throws ServiceException {
067        if (classes != null) {
068            for (Class<? extends ActionExecutor> executorClass : classes) {
069                register(executorClass);
070            }
071        }
072    }
073
074    public void destroy() {
075        ActionExecutor.enableInit();
076        ActionExecutor.resetInitInfo();
077        ActionExecutor.disableInit();
078        executors = null;
079    }
080
081    public Class<? extends Service> getInterface() {
082        return ActionService.class;
083    }
084
085    public void register(Class<? extends ActionExecutor> klass) throws ServiceException {
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    Set<String> getActionTypes() {
105        return executors.keySet();
106    }
107}