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.action.decision;
019
020 import org.apache.oozie.client.WorkflowAction;
021 import org.apache.oozie.action.ActionExecutor;
022 import org.apache.oozie.action.ActionExecutorException;
023 import org.apache.oozie.util.XLog;
024 import org.apache.oozie.util.XmlUtils;
025 import org.jdom.Element;
026 import org.jdom.JDOMException;
027 import org.jdom.Namespace;
028
029 import java.util.List;
030
031 public class DecisionActionExecutor extends ActionExecutor {
032 public static final String ACTION_TYPE = "switch";
033
034 private static final String TRUE = "true";
035
036 public static final String XML_ERROR = "XML_ERROR";
037
038 public DecisionActionExecutor() {
039 super(ACTION_TYPE);
040 }
041
042 @SuppressWarnings("unchecked")
043 public void start(Context context, WorkflowAction action) throws ActionExecutorException {
044 XLog log = XLog.getLog(getClass());
045 log.trace("start() begins");
046 try {
047 String confStr = action.getConf();
048 context.setStartData("-", "-", "-");
049 Element conf = XmlUtils.parseXml(confStr);
050 Namespace ns = conf.getNamespace();
051
052 String externalState = null;
053
054 for (Element eval : (List<Element>) conf.getChildren("case", ns)) {
055 if (TRUE.equals(eval.getTextTrim())) {
056 externalState = eval.getAttributeValue("to");
057 break;
058 }
059 }
060 if (externalState == null) {
061 Element def = conf.getChild("default", ns);
062 if (def != null) {
063 externalState = def.getAttributeValue("to");
064 }
065 }
066
067 if (externalState == null) {
068 throw new IllegalStateException("Transition cannot be NULL");
069 }
070 // for decision we are piggybacking on external status to transfer the transition,
071 // the {@link ActionEndCommand} does the special handling of setting it as signal value.
072 context.setExecutionData(externalState, null);
073 }
074 catch (JDOMException ex) {
075 throw new ActionExecutorException(ActionExecutorException.ErrorType.FAILED, XML_ERROR, ex.getMessage(), ex);
076 }
077 finally {
078 log.trace("start() ends");
079 }
080 }
081
082 public void end(Context context, WorkflowAction action) throws ActionExecutorException {
083 context.setEndData(WorkflowAction.Status.OK, action.getExternalStatus());
084 }
085
086 public void check(Context context, WorkflowAction action) throws ActionExecutorException {
087 throw new UnsupportedOperationException();
088 }
089
090 public void kill(Context context, WorkflowAction action) throws ActionExecutorException {
091 throw new UnsupportedOperationException();
092 }
093
094 public boolean isCompleted(String externalStatus) {
095 return true;
096 }
097
098 }