public void setInput(Configuration conf, Map<String, Collection<Scan>> snapshotScans,
    Path restoreDir) throws IOException {
    Path rootDir = CommonFSUtils.getRootDir(conf);
    FileSystem fs = rootDir.getFileSystem(conf);

    setSnapshotToScans(conf, snapshotScans);
    Map<String, Path> restoreDirs =
      generateSnapshotToRestoreDirMapping(snapshotScans.keySet(), restoreDir);
    setSnapshotDirs(conf, restoreDirs);
    restoreSnapshots(conf, restoreDirs, fs);
  }
Configure conf to read from snapshotScans, with snapshots restored to a subdirectory of
restoreDir.
<p/>
Sets: {@link #RESTORE_DIRS_KEY}, {@link #SNAPSHOT_TO_SCANS_KEY}
hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/MultiTableSnapshotInputFormatImpl.java