public static BigDecimal toBigDecimal(byte[] bytes, int offset, final int length) {
    if (bytes == null || length < SIZEOF_INT + 1 || (offset + length > bytes.length)) {
      return null;
    }

    int scale = toInt(bytes, offset);
    byte[] tcBytes = new byte[length - SIZEOF_INT];
    System.arraycopy(bytes, offset + SIZEOF_INT, tcBytes, 0, length - SIZEOF_INT);
    return new BigDecimal(new BigInteger(tcBytes), scale);
  }
Converts a byte array to a BigDecimal value
hbase-common/src/main/java/org/apache/hadoop/hbase/util/Bytes.java