public static void setInput(Configuration conf, String snapshotName, Path restoreDir)
    throws IOException {
    setInput(conf, snapshotName, restoreDir, null, 1);
  }
Configures the job to use TableSnapshotInputFormat to read from a snapshot.
@param conf         the job to configuration
@param snapshotName the name of the snapshot to read from
@param restoreDir   a temporary directory to restore the snapshot into. Current user should
                    have write permissions to this directory, and this should not be a
                    subdirectory of rootdir. After the job is finished, restoreDir can be
                    deleted.
@throws IOException if an error occurs
hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/TableSnapshotInputFormatImpl.java