java CRC7校验

在java中进行CRC7校验,代码如下; 

    //CRC7校验
        public static byte crc7Check(byte[] by1)...{
            byte[] crc7byte=...{0x00,0x12,0x24,0x36,0x48,0x5a,0x6c,0x7e,
                           0x19,0x0b,0x3d,0x2f,0x51,0x43,0x75,0x67,
                           0x32,0x20,0x16,0x04,0x7a,0x68,0x5e,0x4c,
                           0x2b,0x39,0x0f,0x1d,0x63,0x71,0x47,0x55,
                           0x64,0x76,0x40,0x52,0x2c,0x3e,0x08,0x1a,
                           0x7d,0x6f,0x59,0x4b,0x35,0x27,0x11,0x03,
                           0x56,0x44,0x72,0x60,0x1e,0x0c,0x3a,0x28,
                           0x4f,0x5d,0x6b,0x79,0x07,0x15,0x23,0x31,
                           0x41,0x53,0x65,0x77,0x09,0x1b,0x2d,0x3f,
                           0x58,0x4a,0x7c,0x6e,0x10,0x02,0x34,0x26,
                           0x73,0x61,0x57,0x45,0x3b,0x29,0x1f,0x0d,
                           0x6a,0x78,0x4e,0x5c,0x22,0x30,0x06,0x14,
                           0x25,0x37,0x01,0x13,0x6d,0x7f,0x49,0x5b,
                           0x3c,0x2e,0x18,0x0a,0x74,0x66,0x50,0x42,
                           0x17,0x05,0x33,0x21,0x5f,0x4d,0x7b,0x69,
                           0x0e,0x1c,0x2a,0x38,0x46,0x54,0x62,0x70};
            
            byte result=0;
    
            for(int i=0;i<by1.length-2;i++)...{
                
                if(by1[i]<0)...{
                    result= (byte) crc7byte[((256+by1[i])/2)^result];
                }else...{
                    result= (byte) crc7byte[(by1[i]/2)^result];
                }
                byte b=(byte)(by1[i]&(byte)0x01);
               if(b==0)...{   
                   result^=0X00;
               }else...{
                   result^=0x09;
                   
               }
            }    
            return (byte) ((result*2)+0x01);    
        }