Java Code Examples for org.apache.hadoop.conf.Configuration

/**
 * Add an file path to the current set of classpath entries. It adds the file to cache as well.
 * <p/>
 * This is copied from Hadoop 0.20.2 o.a.h.filecache.DistributedCache so we can inject the correct path separator for
 * the environment the cluster is executing in. See {@link #getClusterPathSeparator()}.
 *
 * @param file Path of the file to be added
 * @param conf Configuration that contains the classpath setting
 */
public void addFileToClassPath( Path file, Configuration conf )
  throws IOException {

  // Save off the classloader, to make sure the version info can be loaded successfully from the hadoop-common JAR
  ClassLoader cl = Thread.currentThread().getContextClassLoader();
  Thread.currentThread().setContextClassLoader( VersionInfo.class.getClassLoader() );

  // Restore the original classloader
  Thread.currentThread().setContextClassLoader( cl );

  String classpath = conf.get( "mapred.job.classpath.files" );
  conf.set( "mapred.job.classpath.files", classpath == null ? file.toString()
    : classpath + getClusterPathSeparator() + file.toString() );
  FileSystem fs = FileSystem.get( conf );
  URI uri = fs.makeQualified( file ).toUri();

  org.apache.hadoop.mapreduce.filecache.DistributedCache.addCacheFile( uri, conf );
}
 

private void setTokenRefreshCredentials(LogicalPlan dag, Configuration conf) throws IOException
{
  String principal = conf.get(StramClientUtils.TOKEN_REFRESH_PRINCIPAL, StramUserLogin.getPrincipal());
  String keytabPath = conf.get(StramClientUtils.TOKEN_REFRESH_KEYTAB, conf.get(StramClientUtils.KEY_TAB_FILE));
  if (keytabPath == null) {
    String keytab = StramUserLogin.getKeytab();
    if (keytab != null) {
      Path localKeyTabPath = new Path(keytab);
      try (FileSystem fs = StramClientUtils.newFileSystemInstance(conf)) {
        Path destPath = new Path(StramClientUtils.getApexDFSRootDir(fs, conf), localKeyTabPath.getName());
        if (!fs.exists(destPath)) {
          fs.copyFromLocalFile(false, false, localKeyTabPath, destPath);
        }
        keytabPath = destPath.toString();
      }
    }
  }
  LOG.debug("User principal is {}, keytab is {}", principal, keytabPath);
  if ((principal != null) && (keytabPath != null)) {
    dag.setAttribute(LogicalPlan.PRINCIPAL, principal);
    dag.setAttribute(LogicalPlan.KEY_TAB_FILE, keytabPath);
  } else {
    LOG.warn("Credentials for refreshing tokens not available, application may not be able to run indefinitely");
  }
}
 

@Override
public WriteContext init(Configuration configuration) {
  if (this.protocolFactory == null) {
    try {
      this.protocolFactory = getTProtocolFactoryClass(configuration).newInstance();
    } catch (InstantiationException | IllegalAccessException e) {
      throw new RuntimeException(e);
    }
  }
  if (thriftClass != null) {
    TBaseWriteSupport.setThriftClass(configuration, thriftClass);
  } else {
    thriftClass = TBaseWriteSupport.getThriftClass(configuration);
  }
  this.thriftStruct = ThriftSchemaConverter.toStructType(thriftClass);
  this.schema = ThriftSchemaConverter.convertWithoutProjection(thriftStruct);
  if (buffered) {
    readToWrite = new BufferedProtocolReadToWrite(thriftStruct, errorHandler);
  } else {
    readToWrite = new ProtocolReadToWrite();
  }
  return thriftWriteSupport.init(configuration);
}
 

@Test(expected = IOException.class)
public void testGetAllShardedTableMapFilesWithoutPath() throws Exception {
    Configuration conf = new Configuration();
    File tempWorkDir = Files.createTempDir();
    conf.set(FileSystem.FS_DEFAULT_NAME_KEY, tempWorkDir.toURI().toString());
    FileSystem fs = FileSystem.get(tempWorkDir.toURI(), conf);
    fs.setWorkingDirectory(new Path(tempWorkDir.toString()));
    Path workDir = fs.makeQualified(new Path("work"));
    conf.set(ShardedTableMapFile.SPLIT_WORK_DIR, workDir.toString());
    
    conf.set(ShardedDataTypeHandler.SHARDED_TNAMES, "shard_ingest_unit_test_table_1,shard_ingest_unit_test_table_2,shard_ingest_unit_test_table_3");
    
    String[] tableNames = new String[] {TABLE_NAME};
    conf.set(ShardedTableMapFile.TABLE_NAMES, StringUtils.join(",", tableNames));
    ShardedTableMapFile.setupFile(conf);
    ShardedTableMapFile.getShardIdToLocations(conf, TABLE_NAME);
}
 

/**
 * Refresh all user-to-groups mappings.
 * @param conf
 */
public void refresh(Configuration conf) {

  LOG.info("reload staticUserToGroupsMap");
  staticUserToGroupsMap = parseStaticMapping(conf);

  LOG.info("clearing userToGroupsMap cache");
  try {
    impl.cacheGroupsRefresh();
  } catch (IOException e) {
    LOG.warn("Error refreshing groups cache", e);
  }
  cache.invalidateAll();
  if(isNegativeCacheEnabled()) {
    negativeCache.clear();
  }
}
 

/**
 * Callers must afterward call {@link HBaseTestingUtility#closeRegionAndWAL(HRegion)}
 */
private HRegion initHRegion(byte[] tableName, String callingMethod, Configuration conf,
    String family, BlockCache blockCache) throws IOException {
  TableDescriptorBuilder builder =
      TableDescriptorBuilder.newBuilder(TableName.valueOf(tableName));
  for (int i = 0; i < BLOOM_TYPE.length; i++) {
    BloomType bloomType = BLOOM_TYPE[i];
    builder.setColumnFamily(
        ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes(family + "_" + bloomType))
            .setBlocksize(1).setBloomFilterType(bloomType).build());
  }
  RegionInfo info = RegionInfoBuilder.newBuilder(TableName.valueOf(tableName)).build();
  Path path = new Path(DIR + callingMethod);
  if (blockCache != null) {
    return HBaseTestingUtility.createRegionAndWAL(info, path, conf, builder.build(), blockCache);
  } else {
    return HBaseTestingUtility.createRegionAndWAL(info, path, conf, builder.build());
  }
}
 

@Override
protected void configureServlets() {

  appContext = new MockHistoryContext(0, 1, 2, 1, false);
  webApp = mock(HsWebApp.class);
  when(webApp.name()).thenReturn("hsmockwebapp");

  bind(JAXBContextResolver.class);
  bind(HsWebServices.class);
  bind(GenericExceptionHandler.class);
  bind(WebApp.class).toInstance(webApp);
  bind(AppContext.class).toInstance(appContext);
  bind(HistoryContext.class).toInstance(appContext);
  bind(Configuration.class).toInstance(conf);

  serve("/*").with(GuiceContainer.class);
}
 

private void mockHdfs() throws Exception {
    PowerMockito.mockStatic(HDFSUtil.class);
    hdfs = mock(FileSystem.class);
    when(HDFSUtil.getFileSystem(any(Configuration.class))).thenReturn(hdfs);
    FileStatus fileDirStatus = new FileStatus(100l, true, 3, 1000l, new Date().getTime(), new Path("/user/history/done/2016/12/09/000508"));
    when(hdfs.listStatus(any(Path.class))).thenReturn(new FileStatus[] {fileDirStatus});
    FileStatus filePartitionStatus = new FileStatus(100l, false, 3, 1000l, new Date().getTime(), new Path("/user/history/done/2016/12/09/000508/job_1479206441898_508949-1481299030929-testhistory.jhist"));
    when(hdfs.listStatus(any(Path.class), any(PathFilter.class))).thenReturn(new FileStatus[] {filePartitionStatus});
    Path historyFilePath = mock(Path.class);
    Path historyConfPath = mock(Path.class);
    PowerMockito.whenNew(Path.class).withArguments("/mr-history/done/2016/12/12/000508/job_1479206441898_508949-1481299030929-testhistory.jhist").thenReturn(historyFilePath);
    PowerMockito.whenNew(Path.class).withArguments("/mr-history/done/2016/12/12/000508/job_1479206441898_508949_conf.xml").thenReturn(historyConfPath);

    when((InputStream) hdfs.open(historyFilePath)).thenReturn(this.getClass().getResourceAsStream("job_1479206441898_508949-1481299030929-testhistory.jhist"));
    when((InputStream) hdfs.open(historyConfPath)).thenReturn(this.getClass().getResourceAsStream("job_1479206441898_508949_conf.xml"));
}
 

@Test
public void testSaveWithIngest() throws Exception {
    EsAssume.versionOnOrAfter(EsMajorVersion.V_5_X, "Ingest Supported in 5.x and above only");

    Configuration conf = createConf();

    RestUtils.ExtendedRestClient client = new RestUtils.ExtendedRestClient();
    String prefix = "mrnewapi";
    String pipeline = "{\"description\":\"Test Pipeline\",\"processors\":[{\"set\":{\"field\":\"pipeTEST\",\"value\":true,\"override\":true}}]}";
    client.put("/_ingest/pipeline/" + prefix + "-pipeline", StringUtils.toUTF(pipeline));
    client.close();

    conf.set(ConfigurationOptions.ES_RESOURCE, resource("mrnewapi-ingested", "data", clusterInfo.getMajorVersion()));
    conf.set(ConfigurationOptions.ES_INGEST_PIPELINE, "mrnewapi-pipeline");
    conf.set(ConfigurationOptions.ES_NODES_INGEST_ONLY, "true");

    runJob(conf);
}
 

public SkippingReduceValuesIterator(RawKeyValueIterator in,
    RawComparator<KEY> comparator, Class<KEY> keyClass,
    Class<VALUE> valClass, Configuration conf, TaskReporter reporter,
    TaskUmbilicalProtocol umbilical) throws IOException {
  super(in, comparator, keyClass, valClass, conf, reporter);
  this.umbilical = umbilical;
  this.skipGroupCounter =
    reporter.getCounter(Counter.REDUCE_SKIPPED_GROUPS);
  this.skipRecCounter =
    reporter.getCounter(Counter.REDUCE_SKIPPED_RECORDS);
  this.toWriteSkipRecs = toWriteSkipRecs() &&
    SkipBadRecords.getSkipOutputPath(conf)!=null;
  this.keyClass = keyClass;
  this.valClass = valClass;
  this.reporter = reporter;
  skipIt = getSkipRanges().skipRangeIterator();
  mayBeSkip();
}
 

/**
 * 
 * @param path
 * @param conf
 * @param logger
 * @param version - is being used only for testing. Should be passed as null for other purposes. 
 * @return SequenceFile.Writer 
 * @throws IOException
 */
public static SequenceFile.Writer getSequenceFileWriter(Path path, 
  Configuration conf, LogWriterI18n logger, Version version) throws IOException {
  Option optPath = SequenceFile.Writer.file(path);
  Option optKey = SequenceFile.Writer.keyClass(BytesWritable.class);
  Option optVal = SequenceFile.Writer.valueClass(BytesWritable.class);
  Option optCom = withCompression(logger);
  logger.fine("Started creating hoplog " + path);
  
  if (version == null)
    version = Version.CURRENT;
  //Create a metadata option with the gemfire version, for future versioning
  //of the key and value format
  SequenceFile.Metadata metadata = new SequenceFile.Metadata();
  metadata.set(new Text(Meta.GEMFIRE_VERSION.name()), new Text(String.valueOf(version.ordinal())));
  Option optMeta = SequenceFile.Writer.metadata(metadata);
  
  SequenceFile.Writer writer = SequenceFile.createWriter(conf, optPath, optKey, optVal, optCom, optMeta);
  
  return writer;
}
 

/** Get an array of FilterConfiguration specified in the conf */
private static FilterInitializer[] getFilterInitializers(Configuration conf) {
  if (conf == null) {
    return null;
  }

  Class<?>[] classes = conf.getClasses(FILTER_INITIALIZER_PROPERTY);
  if (classes == null) {
    return null;
  }

  FilterInitializer[] initializers = new FilterInitializer[classes.length];
  for(int i = 0; i < classes.length; i++) {
    initializers[i] = (FilterInitializer)ReflectionUtils.newInstance(
        classes[i], conf);
  }
  return initializers;
}
 

public static void main(String[] args) throws Exception {
    Configuration conf = new Configuration();
    if (args.length < 2) {
        System.err.println("Usage: LinkCountHDFS inputDir outputDir");
        System.exit(2);
    }
    String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
    
    Job job = Job.getInstance(conf, "link count hdfs");
    job.setJarByClass(LinkCountHDFS.class);
    job.setInputFormatClass(HDFSInputFormat.class);
    job.setMapperClass(RefMapper.class);
    job.setMapOutputKeyClass(Text.class);
    job.setMapOutputValueClass(IntWritable.class);
    
    job.setReducerClass(IntSumReducer.class);
    job.setOutputFormatClass(TextOutputFormat.class);
    job.setOutputKeyClass(Text.class);
    job.setOutputValueClass(IntWritable.class);
    HDFSInputFormat.setInputPaths(job, new Path(otherArgs[0]));
    FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));

    System.exit(job.waitForCompletion(true) ? 0 : 1);
}
 

/**
 * Construct an IFile Reader.
 * 
 * @param conf Configuration File 
 * @param in   The input stream
 * @param length Length of the data in the stream, including the checksum
 *               bytes.
 * @param codec codec
 * @param readsCounter Counter for records read from disk
 * @throws IOException
 */
public Reader(Configuration conf, FSDataInputStream in, long length, 
              CompressionCodec codec,
              Counters.Counter readsCounter) throws IOException {
  readRecordsCounter = readsCounter;
  checksumIn = new IFileInputStream(in,length, conf);
  if (codec != null) {
    decompressor = CodecPool.getDecompressor(codec);
    if (decompressor != null) {
      this.in = codec.createInputStream(checksumIn, decompressor);
    } else {
      LOG.warn("Could not obtain decompressor from CodecPool");
      this.in = checksumIn;
    }
  } else {
    this.in = checksumIn;
  }
  this.dataIn = new DataInputStream(this.in);
  this.fileLength = length;
  
  if (conf != null) {
    bufferSize = conf.getInt("io.file.buffer.size", DEFAULT_BUFFER_SIZE);
  }
}
 

@Test
public void testSimpleMapCast() throws IOException, ParserException {
    PigServer pig = new PigServer(ExecType.LOCAL, new Properties());
    String[] input = {
            "[key#1,key2#2]",
            "[key#2]",
    };

    Util.createInputFile(FileSystem.getLocal(new Configuration()), tmpDirName + "/testSimpleMapCast", input);

    String query =
        "a = load '" + tmpDirName + "/testSimpleMapCast' as (m);" +
        "b = foreach a generate ([int])m;";
    Util.registerMultiLineQuery(pig, query);
    Schema sch = pig.dumpSchema("b");
    assertEquals("Checking expected schema",sch.toString(), "{m: map[int]}");
    Iterator<Tuple> it = pig.openIterator("b");

    Assert.assertTrue(it.hasNext());
    Tuple t = it.next();
    Assert.assertTrue(t.size()==1);
    Assert.assertTrue(t.get(0) instanceof Map);
    Assert.assertTrue(((Map)t.get(0)).containsKey("key"));
    Assert.assertTrue(((Map)t.get(0)).containsKey("key2"));
    Assert.assertTrue(((Map)t.get(0)).get("key") instanceof Integer);
    Assert.assertTrue(((Map)t.get(0)).get("key").toString().equals("1"));
    Assert.assertTrue(((Map)t.get(0)).get("key2") instanceof Integer);
    Assert.assertTrue(((Map)t.get(0)).get("key2").toString().equals("2"));

    Assert.assertTrue(it.hasNext());
    t = it.next();
    Assert.assertTrue(((Map)t.get(0)).containsKey("key"));
    Assert.assertTrue(((Map)t.get(0)).get("key") instanceof Integer);
    Assert.assertTrue(((Map)t.get(0)).get("key").toString().equals("2"));

    Assert.assertFalse(it.hasNext());
}
 

private void testCompressByName(String codec, Configuration conf) throws Exception {
	CompressWriterFactory<String> writer = CompressWriters.forExtractor(new DefaultExtractor<String>())
		.withHadoopCompression(codec, conf);
	List<String> lines = Arrays.asList("line1", "line2", "line3");

	File directory = prepareCompressedFile(writer, lines);

	validateResults(directory, lines, new CompressionCodecFactory(conf).getCodecByName(codec));
}
 

/**
 * Helper method that returns avro reader for the given avro file.
 * If file name ends in 'gz' then returns the GZIP version, otherwise gives the regular reader.
 *
 * @param avroFile File to read
 * @return Avro reader for the file.
 * @throws IOException exception when accessing to IO
 */
protected DataFileStream<GenericRecord> getAvroReader(Path avroFile)
    throws IOException {
  FileSystem fs = FileSystem.get(new Configuration());
  if (avroFile.getName().endsWith("gz")) {
    return new DataFileStream<>(new GZIPInputStream(fs.open(avroFile)), new GenericDatumReader<>());
  } else {
    return new DataFileStream<>(fs.open(avroFile), new GenericDatumReader<>());
  }
}
 

@Test
public void testInitializePath_failure_bucketNotSpecified() throws Exception {
  List<String> invalidPaths = Arrays.asList("gs:/", "gs:/foo", "gs:/foo/bar", "gs:///");
  for (String path : invalidPaths) {
    URI uri = new URI(path);
    try (GoogleHadoopFileSystem testGhfs = createInMemoryGoogleHadoopFileSystem()) {
      IllegalArgumentException e =
          assertThrows(
              "Path '" + path + "' should be invalid",
              IllegalArgumentException.class,
              () -> testGhfs.initialize(uri, new Configuration()));
      assertThat(e).hasMessageThat().startsWith("No bucket specified in GCS URI:");
    }
  }
}
 

public static void main(String[] args) throws Exception
{
  LocalMode lma = LocalMode.newInstance();
  Configuration conf = new Configuration(false);
  lma.prepareDAG(new WindowedMergeOperatorTestApplication(), conf);
  LocalMode.Controller lc = lma.getController();
  lc.run(20000);
}
 

private void createTestParquetFile() throws IOException {
  File file = parquetFile();
  Path fsPath = new Path(file.getPath());
  Configuration conf = new Configuration();

  MessageType schema = createSchema();
  SimpleGroupFactory fact = new SimpleGroupFactory(schema);
  GroupWriteSupport.setSchema(schema, conf);

  try (
    ParquetWriter<Group> writer = new ParquetWriter<>(
      fsPath,
      new GroupWriteSupport(),
      CompressionCodecName.UNCOMPRESSED,
      1024,
      1024,
      512,
      true,
      false,
      ParquetProperties.WriterVersion.PARQUET_2_0,
      conf)) {
    for (int i = 0; i < 10; i++) {
      final byte[] bytes = new byte[12];
      ThreadLocalRandom.current().nextBytes(bytes);

      writer.write(fact.newGroup()
       .append(INT32_FIELD, 32 + i)
       .append(INT64_FIELD, 64L + i)
       .append(FLOAT_FIELD, 1.0f + i)
       .append(DOUBLE_FIELD, 2.0d + i)
       .append(BINARY_FIELD, Binary.fromString(COLORS[i % COLORS.length]))
       .append(FIXED_LEN_BYTE_ARRAY_FIELD,
         Binary.fromConstantByteArray(bytes)));
    }
  }
}
 

public NullScanner(Configuration conf, Schema schema, TableMeta meta, Fragment fragment) {
  this.conf = conf;
  this.meta = meta;
  this.schema = schema;
  this.fragment = fragment;
  this.tableStats = new TableStats();
  this.columnNum = this.schema.size();
}
 

/**
 * Constructor with Conf object
 *
 * @param cfg the {@link Configuration} object to use
 */
public RefreshHFilesClient(Configuration cfg) {
  try {
    this.connection = ConnectionFactory.createConnection(cfg);
  } catch (IOException e) {
    throw new RuntimeException(e);
  }
}
 

@Override
protected void doSetup(Context context) throws IOException {
    Configuration conf = context.getConfiguration();
    bindCurrentConfiguration(conf);
    config = AbstractHadoopJob.loadKylinPropsAndMetadata();

    cubeName = conf.get(BatchConstants.CFG_CUBE_NAME);
    cube = CubeManager.getInstance(config).getCube(cubeName);
    cubeDesc = cube.getDescriptor();
    cubeSeg = cube.getSegmentById(conf.get(BatchConstants.CFG_CUBE_SEGMENT_ID));
    flatTableInputFormat = MRUtil.getBatchCubingInputSide(cubeSeg).getFlatTableInputFormat();

    intermediateTableDesc = new CubeJoinedFlatTableEnrich(EngineFactory.getJoinedFlatTableDesc(cubeSeg), cubeDesc);

    globalColumns = cubeDesc.getAllGlobalDictColumns();
    globalColumnIndex = new int[globalColumns.size()];
    globalColumnValues = Lists.newArrayListWithExpectedSize(globalColumns.size());

    for (int i = 0; i < globalColumns.size(); i++) {
        TblColRef colRef = globalColumns.get(i);
        int columnIndexOnFlatTbl = intermediateTableDesc.getColumnIndex(colRef);
        globalColumnIndex[i] = columnIndexOnFlatTbl;
        globalColumnValues.add(Sets.<String> newHashSet());
    }

    splitKey = DictionaryGetterUtil.getInputSplitSignature(cubeSeg, context.getInputSplit());
}
 

/**
 * Dumps the full job logs for a particular application to stdout.
 *
 * @param applicationId application to dump logs for
 */
public static void dumpFullLogs(Configuration cfg, ApplicationId applicationId) {
  LogCLIHelpers logCliHelpers = new LogCLIHelpers();
  // TODO: Add the proper base dir settings etc...

  logCliHelpers.setConf(cfg);
  try {
    logCliHelpers.dumpAllContainersLogs(
        applicationId, cfg.get(SPYDRA_HISTORY_USERNAME_PROPERTY), System.out);
  } catch (IOException e) {
    logger.error("Failed dumping log files for application " + applicationId.toString(), e);
  }
}
 

private static void checkPaths(Configuration conf, List<Path> paths) throws
IOException {
  for (Path p : paths) {
    FileSystem fs = p.getFileSystem(conf);
    if (!fs.exists(p)) {
      throw new FileNotFoundException("Source " + p + " does not exist.");
    }
  }
}
 

@Before
public void setUp() throws Exception {
  conf = new Configuration();
  cluster = new MiniDFSCluster.Builder(conf).numDataNodes(REPLICATION)
      .build();
  cluster.waitActive();
  fsn = cluster.getNamesystem();
  hdfs = cluster.getFileSystem();
  hdfs.mkdirs(dir);
}
 

public Reader(Configuration conf, Option... opts) throws IOException {
  // Look up the options, these are null if not set
  FileOption fileOpt = Options.getOption(FileOption.class, opts);
  InputStreamOption streamOpt =
      Options.getOption(InputStreamOption.class, opts);
  StartOption startOpt = Options.getOption(StartOption.class, opts);
  LengthOption lenOpt = Options.getOption(LengthOption.class, opts);
  BufferSizeOption bufOpt = Options.getOption(BufferSizeOption.class, opts);
  OnlyHeaderOption headerOnly =
      Options.getOption(OnlyHeaderOption.class, opts);
  // check for consistency
  if ((fileOpt == null) == (streamOpt == null)) {
    throw new
        IllegalArgumentException("File or stream option must be specified");
  }
  if (fileOpt == null && bufOpt != null) {
    throw new IllegalArgumentException("buffer size can only be set when" +
                                       " a file is specified.");
  }
  // figure out the real values
  Path filename = null;
  FSDataInputStream file;
  final long len;
  if (fileOpt != null) {
    filename = fileOpt.getValue();
    FileSystem fs = filename.getFileSystem(conf);
    int bufSize = bufOpt == null ? getBufferSize(conf) : bufOpt.getValue();
    len = null == lenOpt
          ? fs.getFileStatus(filename).getLen()
          : lenOpt.getValue();
    file = openFile(fs, filename, bufSize, len);
  } else {
    len = null == lenOpt ? Long.MAX_VALUE : lenOpt.getValue();
    file = streamOpt.getValue();
  }
  long start = startOpt == null ? 0 : startOpt.getValue();
  // really set up
  initialize(filename, file, start, len, conf, headerOnly != null);
}
 

private void enableKeyTabSecurity() throws IOException {

        final String PRINCIPAL = "principal";
        final String KEYTAB = "keyTab";
        // Login with the credentials from the keytab to retrieve the TGT . The
        // renewal of the TGT happens in a Zookeeper thread
        String principal = null;
        String keyTabPath = null;
        AppConfigurationEntry entries[] =
                javax.security.auth.login.Configuration.getConfiguration()
                        .getAppConfigurationEntry("Client");
        LOGGER.info("Security - Fetched App Login Configuration Entries");
        if (entries != null) {
            for (AppConfigurationEntry entry : entries) {
                if (entry.getOptions().get(PRINCIPAL) != null) {
                    principal = (String) entry.getOptions().get(PRINCIPAL);
                }
                if (entry.getOptions().get(KEYTAB) != null) {
                    keyTabPath = (String) entry.getOptions().get(KEYTAB);
                }
            }
            LOGGER.info("Security - Got Principal = " + principal + "");
            if (principal != null && keyTabPath != null) {
                LOGGER.info("Security - Retreiving the TGT with principal:" + principal
                        + " and keytab:" + keyTabPath);
                UserGroupInformation.loginUserFromKeytab(principal, keyTabPath);
                LOGGER.info("Security - Retrieved TGT with principal:" + principal + " and keytab:"
                        + keyTabPath);
            }
        }
    }
 

@Test
public void testHigherMaxThanReducers() throws IllegalAccessException, InstantiationException {
    Configuration conf = new Configuration();
    conf.setInt(PartitionLimiter.MAX_PARTITIONS_PROPERTY, NUM_REDUCERS + 1);
    
    LimitedKeyPartitioner partitioner = LimitedKeyPartitioner.class.newInstance();
    partitioner.setConf(conf);
    assertPartitionsUnderMax(partitioner, NUM_REDUCERS);
}
 

@Test public void testConfigurationUpdate() {
	Configuration conf = new Configuration(false);
	m_limit.applyTo(conf);
	ResourceLimit expected = new ResourceLimit(m_resource, m_value, LimitSource.CONFIG);
	ResourceLimit limit = ResourceLimit.extractFrom(m_resource, conf);
	assertEquals(expected, limit);
}