public static byte[][] makeNAscii(byte[] base, int n) {
    byte[][] ret = new byte[n][];
    for (int i = 0; i < n; i++) {
      byte[] tail = Bytes.toBytes(Integer.toString(i));
      ret[i] = Bytes.add(base, tail);
    }
    return ret;
  }
Generate the given number of unique byte sequences by appending numeric suffixes (ASCII
representations of decimal numbers).
hbase-server/src/test/java/org/apache/hadoop/hbase/HTestConst.java