public static if_icmpeq getInstance(byte[] codes, int offset) throws instructionException {
   if (codes[offset] != ins.opcode)
     throw new instructionException("supplied code is not valid " + ins.mnemonic + " opcode");
   if_icmpeq res = new if_icmpeq();
   res.offset = offset;
   res.opcode = codes[offset++];
   res.branch = Util.byte2Short(codes, offset);
   return res;
 }
 public byte[] getData() {
   return new byte[] {opcode, Util.getHighByte(branch), Util.getLowByte(branch)};
 }