conf.setBoolean(MRJobConfig.MAP_OUTPUT_COMPRESS, true);
TaskAttemptID taskId = new TaskAttemptID();
FakeRecordLLReader reader = new FakeRecordLLReader();
LoadRecordGkNullWriter writer = new LoadRecordGkNullWriter();
OutputCommitter committer = new CustomOutputCommitter();
StatusReporter reporter = new TaskAttemptContextImpl.DummyReporter();
SleepSplit split = getSleepSplit();
MapContext<LongWritable, LongWritable, GridmixKey, NullWritable> mapcontext = new MapContextImpl<LongWritable, LongWritable, GridmixKey, NullWritable>(
conf, taskId, reader, writer, committer, reporter, split);
Context context = new WrappedMapper<LongWritable, LongWritable, GridmixKey, NullWritable>()
.getMapContext(mapcontext);