Masalah porting Delphi ke Java lainnya

Saya mem-porting aplikasi lama yang ditulis dalam Delphi ke Java. Saya mengalami masalah dengan fungsi ini, yang menghitung CRC dari pesan yang dikirimkan.

Ini kode aslinya:

       if(ReceivedMessage[slot].Message[1] = $FD) and
          (ReceivedMessage[slot].MessageLength in [1..16]) and
          (ReceivedMessage[slot].Message[counter] = $FF) then
       begin
        index := 2;
        ReceivedMessage[slot].DataReady := TRUE;

        for counter := 1 to ReceivedMessage[slot].MessageLength do
        begin
          Inc(index);

          if ReceivedMessage[slot].Message[index] < $F8 then
            ReceivedMessage[slot].Data[counter] := ReceivedMessage[slot].Message[index]
          else
          if ReceivedMessage[slot].Message[index] = $F8 then
          begin
            Inc(index);

            ReceivedMessage[slot].Data[counter] := ReceivedMessage[slot].Message[index] or $F0;
          end
          else
            ReceivedMessage[slot].DataReady := FALSE;  // Invalid data
        end;

        if ReceivedMessage[slot].DataReady = TRUE then
        begin
          Inc(index);

          if ReceivedMessage[slot].Message[index] < $F8 then
            ReceivedMessage[slot].CRC := ReceivedMessage[slot].Message[index] shl 8
          else
          if ReceivedMessage[slot].Message[index] = $F8 then
          begin
            Inc(index);

            ReceivedMessage[slot].CRC := (ReceivedMessage[slot].Message[index] or $F0) shl 8;
          end;

          Inc(index);

          if ReceivedMessage[slot].Message[index] < $F8 then
            ReceivedMessage[slot].CRC := ReceivedMessage[slot].CRC or ReceivedMessage[slot].Message[index]
          else
          if ReceivedMessage[slot].Message[index] = $F8 then
          begin
            Inc(index);

            ReceivedMessage[slot].CRC := ReceivedMessage[slot].CRC or        ReceivedMessage[slot].Message[index] or $F0;
          end;

Dan inilah kode Java saya:

 if(array[1]==0xFD && (array[2]>0 && array[2]<17) && array[pos]==(byte)0xFF)
 {
index=2;
for(int counter=1;counter<splMsg.nbytes+1;counter++)
{
     index++;
 if(array[index]<0xF8)
     data[counter]=array[index];
 else
     if(array[index]==0xF8)
     {
      index++;
      data[counter]=(byte)(array[index] | 0xF0);
     }
     else
         return 0xFC; 
}


index++;
short crc=0x0000;

if(array[index]<0xF8)
     crc=(short) (array[index]<<8);
else
   if(array[index]==0xF8)
   {
    index++;
    crc=(short)((array[index] | 0xF0) << 8);
   }
index++;
if(array[index]<0xF8)
    crc=(short) (crc | array[index]);
else
   if(array[index]==0xF8)
   {
    index++;
    crc=(short)(crc | array[index] | 0xF0);
   }

msgcrc=new byte[] {(byte)(crc >> 8 & 0xff),(byte)(crc & 0xff)};

Fungsi saya mengembalikan kode CRC yang dikirimkan paling sering, tetapi terkadang gagal dan mengembalikan dua byte terakhir pesan. 3 byte terakhir dari pesan adalah kode CRC (2 byte) dan byte akhir pesan 0xff.

Ada bantuan?

Terima kasih, Pedro