code: private String decodeSingleCID(byte[] bytes, int offset, int len){
          if (toUnicodeCmap != null){
              if (offset + len > bytes.length)
                  throw new ArrayIndexOutOfBoundsException("Invalid index: " + offset + len);
              return toUnicodeCmap.lookup(bytes, offset, len);
          }
  
          if (len == 1){
              return new String(cidbyte2uni, 0xff & bytes[offset], 1);
          }
          
          throw new Error("Multi-byte glyphs not implemented yet");
      }
docs: Decodes a single CID (represented by one or two bytes) to a unicode String.
  @param bytes		the bytes making up the character code to convert
  @param offset	an offset
  @param len		a length
  @return	a String containing the encoded form of the input bytes using the font's encoding.