TestDatamerge.java 文件源码

public void testEmptyJoin() throws Exception {
  JobConf job = new JobConf();
  Path base = cluster.getFileSystem().makeQualified(new Path("/empty"));
  Path[] src = { new Path(base,"i0"), new Path("i1"), new Path("i2") };
  job.set("mapreduce.join.expr", CompositeInputFormat.compose("outer",
      Fake_IF.class, src));
  job.setInputFormat(CompositeInputFormat.class);
  FileOutputFormat.setOutputPath(job, new Path(base, "out"));

  job.setMapperClass(IdentityMapper.class);
  job.setReducerClass(IdentityReducer.class);
  job.setOutputKeyClass(IncomparableKey.class);
  job.setOutputValueClass(NullWritable.class);

  JobClient.runJob(job);
  base.getFileSystem(job).delete(base, true);
}