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.command;
019
020/**
021 * Transition command for materialize the job. The derived class has to override these following functions:
022 * <p/>
023 * loadState() : load the job's and/or actions' state
024 * updateJob() : update job status and attributes
025 * StartChildren() : submit or queue commands to start children
026 * notifyParent() : update the status to upstream if any
027 */
028public abstract class MaterializeTransitionXCommand extends TransitionXCommand<Void> {
029
030    /**
031     * The constructor for abstract class {@link MaterializeTransitionXCommand}
032     *
033     * @param name the command name
034     * @param type the command type
035     * @param priority the command priority
036     */
037    public MaterializeTransitionXCommand(String name, String type, int priority) {
038        super(name, type, priority);
039    }
040
041    /**
042     * The constructor for abstract class {@link MaterializeTransitionXCommand}
043     *
044     * @param name the command name
045     * @param type the command type
046     * @param priority the command priority
047     * @param dryrun true if dryrun is enable
048     */
049    public MaterializeTransitionXCommand(String name, String type, int priority, boolean dryrun) {
050        super(name, type, priority, dryrun);
051    }
052
053    /* (non-Javadoc)
054     * @see org.apache.oozie.command.TransitionXCommand#transitToNext()
055     */
056    @Override
057    public void transitToNext() throws CommandException {
058    }
059
060    /**
061     * Materialize the actions for current job
062     * @throws CommandException thrown if failed to materialize
063     */
064    protected abstract void materialize() throws CommandException;
065
066    /* (non-Javadoc)
067     * @see org.apache.oozie.command.TransitionXCommand#execute()
068     */
069    @Override
070    protected Void execute() throws CommandException {
071        try {
072            materialize();
073            updateJob();
074            performWrites();
075        } finally {
076            notifyParent();
077        }
078        return null;
079    }
080
081}