Java tutorial
/** * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.hcatalog.templeton; import java.io.IOException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.mapred.JobID; import org.apache.hadoop.mapred.JobProfile; import org.apache.hadoop.mapred.JobStatus; import org.apache.hadoop.mapred.TempletonJobTracker; import org.apache.hcatalog.templeton.tool.JobState; /** * Fetch the status of a given job id in the queue. */ public class StatusDelegator extends TempletonDelegator { private static final Log LOG = LogFactory.getLog(StatusDelegator.class); public StatusDelegator(AppConfig appConf) { super(appConf); } public QueueStatusBean run(String user, String id) throws NotAuthorizedException, BadParam, IOException, InterruptedException { TempletonJobTracker tracker = null; JobState state = null; try { tracker = new TempletonJobTracker(appConf); JobID jobid = StatusDelegator.StringToJobID(id); if (jobid == null) throw new BadParam("Invalid jobid: " + id); state = new JobState(id, Main.getAppConfigInstance()); return StatusDelegator.makeStatus(tracker, jobid, state); } catch (IllegalStateException e) { throw new BadParam(e.getMessage()); } finally { if (tracker != null) tracker.close(); if (state != null) state.close(); } } public static QueueStatusBean makeStatus(TempletonJobTracker tracker, JobID jobid, String childid, JobState state) throws BadParam, IOException { JobID bestid = jobid; if (childid != null) bestid = StatusDelegator.StringToJobID(childid); JobStatus status = tracker.getJobStatus(bestid); JobProfile profile = tracker.getJobProfile(bestid); if (status == null || profile == null) { if (bestid != jobid) { // Corrupt childid, retry. LOG.error("Corrupt child id " + childid + " for " + jobid); bestid = jobid; status = tracker.getJobStatus(bestid); profile = tracker.getJobProfile(bestid); } } if (status == null || profile == null) // No such job. throw new BadParam("Could not find job " + bestid); return new QueueStatusBean(state, status, profile); } public static QueueStatusBean makeStatus(TempletonJobTracker tracker, JobID jobid, JobState state) throws BadParam, IOException { return makeStatus(tracker, jobid, state.getChildId(), state); } /** * A version of JobID.forName with our app specific error handling. */ public static JobID StringToJobID(String id) throws BadParam { try { return JobID.forName(id); } catch (IllegalArgumentException e) { throw new BadParam(e.getMessage()); } } }