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.hadoop.mapred; import java.io.IOException; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.fs.permission.FsPermission; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.v2.MiniMRYarnCluster; import org.apache.hadoop.util.JarFinder; /** * A MiniMRCluster factory. In MR2, it provides a wrapper MiniMRClientCluster * interface around the MiniMRYarnCluster. While in MR1, it provides such * wrapper around MiniMRCluster. This factory should be used in tests to provide * an easy migration of tests across MR1 and MR2. */ public class MiniMRClientClusterFactory { public static MiniMRClientCluster create(Class<?> caller, int noOfNMs, Configuration conf) throws IOException { return create(caller, caller.getSimpleName(), noOfNMs, conf); } public static MiniMRClientCluster create(Class<?> caller, String identifier, int noOfNMs, Configuration conf) throws IOException { if (conf == null) { conf = new Configuration(); } FileSystem fs = FileSystem.get(conf); Path testRootDir = fs.makeQualified(new Path("target", identifier + "-tmpDir")); Path appJar = new Path(testRootDir, "MRAppJar.jar"); // Copy MRAppJar and make it private. Path appMasterJar = new Path(MiniMRYarnCluster.APPJAR); fs.copyFromLocalFile(appMasterJar, appJar); fs.setPermission(appJar, new FsPermission("744")); Job job = Job.getInstance(conf); job.addFileToClassPath(appJar); Path callerJar = new Path(JarFinder.getJar(caller)); Path remoteCallerJar = new Path(testRootDir, callerJar.getName()); fs.copyFromLocalFile(callerJar, remoteCallerJar); fs.setPermission(remoteCallerJar, new FsPermission("744")); job.addFileToClassPath(remoteCallerJar); MiniMRYarnCluster miniMRYarnCluster = new MiniMRYarnCluster(identifier, noOfNMs); job.getConfiguration().set("minimrclientcluster.caller.name", identifier); job.getConfiguration().setInt("minimrclientcluster.nodemanagers.number", noOfNMs); miniMRYarnCluster.init(job.getConfiguration()); miniMRYarnCluster.start(); return new MiniMRYarnClusterAdapter(miniMRYarnCluster); } }