java3.txt

一个不错的CRC校验码！可以计算16位CRC校验码！

package com.wms.serial; 

/** 
* @author linduo 
* @version 2006/08/25 
*/ 
public class CRC16{ 
public int value; 

public CRC16() 
{ 
value = 0; 
} 

/** update CRC with byte b */ 
public void update(byte aByte) 
{ 
int a, b;

a = (int) aByte; 
for (int count = 7; count >=0; count--) { 
a = a << 1; 
b = (a >>>8) & 1; 
if ((value & 0x8000) != 0) { 
value = ((value << 1) + b) ^ 0x1021; 
} else { 
value = (value << 1) + b; 
} 
} 
value = value & 0xffff; 
return; 
} 

/** reset CRC value to 0 */ 
public void reset() 
{ 
value = 0; 
} 

public int getValue() 
{ 
return value; 
}

public static void main(String[] args) { 
CRC16 crc16 = new CRC16(); 
byte[] b = new byte[]{ 
//(byte) 0xF0,(byte)0xF0,(byte)0xF0,(byte)0x72 
(byte) 0x2C,(byte)0x00,(byte)0xFF,(byte)0xFE 
,(byte) 0xFE,(byte)0x04,(byte)0x00,(byte)0x00 
,(byte) 0x00,(byte)0x00 
}; 
for (int k = 0; k < b.length; k++) 
{ 
crc16.update(b[k]); 
} 
System.out.println(Integer.toHexString(crc16.getValue())); 
System.out.println(Integer.toHexString(b.length)); 
} 
}


文章出处：http://www.diybl.com/course/3_program/java/javajs/2007114/83396.html