因为项目需要CRC16的校验,因此在博客上记录一下这个,貌似在网上挺难找的,
/**
* CRC16相关计算
* CRC16多项式：1021，初值：0000
*/
public class CRC16 {
public static short calCRC16(byte[] datas) {
int crc = 0;
for (int index = 0; index < datas.length; index++) {
crc = update((short) crc, datas[index]);
}
crc = update((short) crc, (byte) 0);
crc = update((short) crc, (byte) 0);
return (short) (crc & (short) 0xffff);
}
public static short calRCR16(byte[] datas, int start) {
int crc = 0;
for (int index = start; index < datas.length; index++) {
crc = update((short) crc, datas[index]);
}
crc = update((short) crc, (byte) 0);
crc = update((short) crc, (byte) 0);
return (short) (crc & (short) 0xffff);
}
public static short update(int crc, byte b) {
int in = b & 0xff | 0x100;
do {
crc <<= 1;
in <<= 1;
if ((in & 0x100) > 0) {
++crc;
}
if ((crc & 0x10000) > 0) {
crc ^= 0x1021;
}
} while ((in & 0x10000) <= 0);
return (short) (crc & 0xffff);
}
}
