private Path createInputFile() throws IOException {
    Path f = new Path(workDir + "/MultiTableInput.txt");
    FileSystem fs = FileSystem.get(mrConf);
    if (fs.exists(f)) {
      fs.delete(f, true);
    }
    OutputStream out = fs.create(f);
    for (int i = 0; i < 3; i++) {
      out.write("a,a\n".getBytes());
    }
    out.close();
    return f;
  }
Create a input file for map

@return absolute path of the file.
@throws IOException if any error encountered
hcatalog/core/src/test/java/org/apache/hive/hcatalog/mapreduce/TestHCatMultiOutputFormat.java