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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package sun.misc;
The CRC-16 class calculates a 16 bit cyclic redundancy check of a set
of bytes. This error detecting code is used to determine if bit rot
has occurred in a byte stream.
/**
* The CRC-16 class calculates a 16 bit cyclic redundancy check of a set
* of bytes. This error detecting code is used to determine if bit rot
* has occurred in a byte stream.
*/
public class CRC16 {
value contains the currently computed CRC, set it to 0 initally /** value contains the currently computed CRC, set it to 0 initally */
public int value;
public CRC16() {
value = 0;
}
update CRC with byte b /** 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 /** reset CRC value to 0 */
public void reset() {
value = 0;
}
}