gbk_bytesCodec constructor
gbk_bytesCodec()
Implementation
gbk_bytesCodec(){
//initialize gbk code maps
_char_to_gbkCode = json_char_to_gbk;
json_gbk_to_char.forEach((sInt, sChar) {
_gbkCode_to_char[int.parse(sInt, radix : 16)] = sChar;
});
}