code: static String numericToTextFormat(byte[] src)
      {
          StringBuffer sb = new StringBuffer(39);
          for (int i = 0; i < (INADDRSZ / INT16SZ); i++) {
              sb.append(Integer.toHexString(((src[i<<1]<<8) & 0xff00)
                                            | (src[(i<<1)+1] & 0xff)));
  
              if (i < (INADDRSZ / INT16SZ) -1 ) {
                 sb.append(":");
              }
          }
          return sb.toString();
      }
docs: /*
  Convert IPv6 binary address into presentation (printable) format.
  
  @param src a byte array representing the IPv6 numeric address
  @return a String representing an IPv6 address in
  textual representation format
  @since 1.4