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.tools; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.mapreduce.Cluster; import org.apache.hadoop.mapreduce.JobSubmissionFiles; import org.apache.hadoop.tools.util.TestDistCpUtils; import org.junit.After; import org.junit.Assert; import org.junit.Before; import org.junit.Test; import java.io.IOException; import java.io.OutputStream; import java.security.Permission; public class TestExternalCall { private static final Log LOG = LogFactory.getLog(TestExternalCall.class); private static FileSystem fs; private static String root; private static Configuration getConf() { Configuration conf = new Configuration(); conf.set("fs.default.name", "file:///"); conf.set("mapred.job.tracker", "local"); return conf; } @Before public void setup() { securityManager = System.getSecurityManager(); System.setSecurityManager(new NoExitSecurityManager()); try { fs = FileSystem.get(getConf()); root = new Path("target/tmp").makeQualified(fs.getUri(), fs.getWorkingDirectory()).toString(); TestDistCpUtils.delete(fs, root); } catch (IOException e) { LOG.error("Exception encountered ", e); } } @After public void tearDown() { System.setSecurityManager(securityManager); } /** * test methods run end execute of DistCp class. silple copy file * @throws Exception */ @Test public void testCleanup() throws Exception { Configuration conf = getConf(); Path stagingDir = JobSubmissionFiles.getStagingDir(new Cluster(conf), conf); stagingDir.getFileSystem(conf).mkdirs(stagingDir); Path soure = createFile("tmp.txt"); Path target = createFile("target.txt"); DistCp distcp = new DistCp(conf, null); String[] arg = { soure.toString(), target.toString() }; distcp.run(arg); Assert.assertTrue(fs.exists(target)); } private Path createFile(String fname) throws IOException { Path result = new Path(root + "/" + fname); OutputStream out = fs.create(result); try { out.write((root + "/" + fname).getBytes()); out.write("\n".getBytes()); } finally { out.close(); } return result; } /** * test main method of DistCp. Method should to call System.exit(). * */ @Test public void testCleanupTestViaToolRunner() throws IOException, InterruptedException { Configuration conf = getConf(); Path stagingDir = JobSubmissionFiles.getStagingDir(new Cluster(conf), conf); stagingDir.getFileSystem(conf).mkdirs(stagingDir); Path soure = createFile("tmp.txt"); Path target = createFile("target.txt"); try { String[] arg = { target.toString(), soure.toString() }; DistCp.main(arg); Assert.fail(); } catch (ExitException t) { Assert.assertTrue(fs.exists(target)); Assert.assertEquals(t.status, 0); Assert.assertEquals(stagingDir.getFileSystem(conf).listStatus(stagingDir).length, 0); } } private SecurityManager securityManager; protected static class ExitException extends SecurityException { private static final long serialVersionUID = -1982617086752946683L; public final int status; public ExitException(int status) { super("There is no escape!"); this.status = status; } } private static class NoExitSecurityManager extends SecurityManager { @Override public void checkPermission(Permission perm) { // allow anything. } @Override public void checkPermission(Permission perm, Object context) { // allow anything. } @Override public void checkExit(int status) { super.checkExit(status); throw new ExitException(status); } } }