static

in hadoop-compat/src/main/java/com/twitter/elephantbird/util/HadoopCompat.java [81:193]
106 lines of code
9 McCabe index (conditional complexity)

  static {
    boolean v21 = true;
    final String PACKAGE = "org.apache.hadoop.mapreduce";
    try {
      Class.forName(PACKAGE + ".task.JobContextImpl");
    } catch (ClassNotFoundException cnfe) {
      v21 = false;
    }
    useV21 = v21;
    Class<?> jobContextCls;
    Class<?> taskContextCls;
    Class<?> taskIOContextCls;
    Class<?> mapContextCls;
    Class<?> genericCounterCls;
    try {
      if (v21) {
        jobContextCls =
          Class.forName(PACKAGE+".task.JobContextImpl");
        taskContextCls =
          Class.forName(PACKAGE+".task.TaskAttemptContextImpl");
        taskIOContextCls =
          Class.forName(PACKAGE+".task.TaskInputOutputContextImpl");
        mapContextCls = Class.forName(PACKAGE + ".task.MapContextImpl");
        genericCounterCls = Class.forName(PACKAGE+".counters.GenericCounter");
      } else {
        jobContextCls =
          Class.forName(PACKAGE+".JobContext");
        taskContextCls =
          Class.forName(PACKAGE+".TaskAttemptContext");
        taskIOContextCls =
          Class.forName(PACKAGE+".TaskInputOutputContext");
        mapContextCls = Class.forName(PACKAGE + ".MapContext");
        genericCounterCls =
            Class.forName("org.apache.hadoop.mapred.Counters$Counter");
      }
    } catch (ClassNotFoundException e) {
      throw new IllegalArgumentException("Can't find class", e);
    }
    try {
      JOB_CONTEXT_CONSTRUCTOR =
        jobContextCls.getConstructor(Configuration.class, JobID.class);
      JOB_CONTEXT_CONSTRUCTOR.setAccessible(true);
      TASK_CONTEXT_CONSTRUCTOR =
        taskContextCls.getConstructor(Configuration.class,
                                      TaskAttemptID.class);
      TASK_CONTEXT_CONSTRUCTOR.setAccessible(true);
      GENERIC_COUNTER_CONSTRUCTOR =
          genericCounterCls.getDeclaredConstructor(String.class,
                                                   String.class,
                                                   Long.TYPE);
      GENERIC_COUNTER_CONSTRUCTOR.setAccessible(true);

      if (useV21) {
        MAP_CONTEXT_CONSTRUCTOR =
          mapContextCls.getDeclaredConstructor(Configuration.class,
                                               TaskAttemptID.class,
                                               RecordReader.class,
                                               RecordWriter.class,
                                               OutputCommitter.class,
                                               StatusReporter.class,
                                               InputSplit.class);
        Method get_counter;
        try {
          get_counter = TaskAttemptContext.class.getMethod("getCounter", String.class, String.class);
        } catch (Exception e) {
          get_counter = TaskInputOutputContext.class.getMethod("getCounter", String.class, String.class);
        }

        GET_COUNTER_METHOD = get_counter;
        GET_COUNTER_ENUM_METHOD         = TaskAttemptContext.class.getMethod("getCounter", Enum.class);
        GET_DEFAULT_BLOCK_SIZE_METHOD   = FileSystem.class.getMethod("getDefaultBlockSize", Path.class);
        GET_DEFAULT_REPLICATION_METHOD  = FileSystem.class.getMethod("getDefaultReplication", Path.class);

      } else {
        MAP_CONTEXT_CONSTRUCTOR =
               mapContextCls.getConstructor(Configuration.class,
                                            TaskAttemptID.class,
                                            RecordReader.class,
                                            RecordWriter.class,
                                            OutputCommitter.class,
                                            StatusReporter.class,
                                            InputSplit.class);

        GET_COUNTER_METHOD      = TaskInputOutputContext.class.getMethod("getCounter",
                                                                  String.class, String.class);
        GET_COUNTER_ENUM_METHOD = TaskInputOutputContext.class.getMethod("getCounter", Enum.class);
        GET_DEFAULT_BLOCK_SIZE_METHOD   = FileSystem.class.getMethod("getDefaultBlockSize");
        GET_DEFAULT_REPLICATION_METHOD  = FileSystem.class.getMethod("getDefaultReplication");
      }

      MAP_CONTEXT_CONSTRUCTOR.setAccessible(true);
      READER_FIELD = mapContextCls.getDeclaredField("reader");
      READER_FIELD.setAccessible(true);
      WRITER_FIELD = taskIOContextCls.getDeclaredField("output");
      WRITER_FIELD.setAccessible(true);

      GET_CONFIGURATION_METHOD  = JobContext.class        .getMethod("getConfiguration");
      SET_STATUS_METHOD         = TaskAttemptContext.class.getMethod("setStatus", String.class);
      GET_TASK_ATTEMPT_ID       = TaskAttemptContext.class.getMethod("getTaskAttemptID");
      INCREMENT_COUNTER_METHOD  = Counter.class           .getMethod("increment", Long.TYPE);
      GET_COUNTER_VALUE_METHOD  = Counter.class           .getMethod("getValue");
      GET_JOB_ID_METHOD         = JobContext.class        .getMethod("getJobID");
      GET_JOB_NAME_METHOD       = JobContext.class        .getMethod("getJobName");
      GET_INPUT_SPLIT_METHOD    = MapContext.class        .getMethod("getInputSplit");

    } catch (SecurityException e) {
      throw new IllegalArgumentException("Can't run constructor ", e);
    } catch (NoSuchMethodException e) {
      throw new IllegalArgumentException("Can't find constructor ", e);
    } catch (NoSuchFieldException e) {
      throw new IllegalArgumentException("Can't find field ", e);
    }
  }