hadoop jar $HADOOP_INSTALL/hadoop-*-examples.jar sort -r 1 \
  -inFormat org.apache.hadoop.mapred.SequenceFileInputFormat \
  -outFormat org.apache.hadoop.mapred.SequenceFileOutputFormat \
  -outKey org.apache.hadoop.io.IntWritable \
  -outValue org.apache.hadoop.io.Text \
  numbers.seq numbers.map