import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.Mapper; public class MyHadoopLibrary { @CustomMapper public static class MyMapper extends Mapper<LongWritable, Text, Text, IntWritable> { // ... } public static void main(String[] args) throws Exception { Configuration conf = new Configuration(); Job job = Job.getInstance(conf, "MyHadoopLibrary"); job.setMapperClass(MyMapper.class); // ... System.exit(job.waitForCompletion(true) ? 0 : 1); } }