Ask how to convert the java code of crc16 to php

Could you tell me how to convert the java code of crc16 to the php Post? Finally, the Post is edited by oelenson from 2014-06-211:49:27? this & nbsp; crc & nbsp; 16 & nbsp; how to convert the java code of to php, and use php & nbsp; the code to be converted is incorrect $ str2AQEBAQEB; $ str2 how can I convert the java code of crc 16 to php?

This post was last edited by oelenson at 12:49:27

How can I convert the java code of crc 16 to php?

$ Str2 = 'aqebaqeb ';
$ Str2 = base64_decode ($ str2 );


Java code

public static int CRC16(final byte[] buffer) {
int crc = 0xffff;

for (int i = 0; i < buffer.length; i++) {
crc = ((crc >>> 8) | (crc << 8)) & 0xffff;
crc ^= (buffer[i] & 0xff);
crc ^= ((crc & 0xff) >> 4);
crc ^= (crc << 12) & 0xffff;
crc ^= ((crc & 0xff) << 5) & 0xffff;
}
crc &= 0xffff;

return crc;
}

function uRShift($a, $b)
{
    if($b == 0) return $a;
    return ($a >> $b) & ~(1<<(8*PHP_INT_SIZE-1)>>($b-1));
} 



function crc16($buffer) {
 $crc = 0xffff;
 for ($i = 0; $i < strlen($buffer); $i++) {
 $crc = ((uRShift($crc,8)) | ($crc << 8)) & 0xffff;
 $crc ^= ($buffer[$i] & 0xff);
 $crc ^= (($crc & 0xff) >> 4);
 $crc ^= ($crc << 12) & 0xffff;
 $crc ^= (($crc & 0xff) << 5) & 0xffff;
 }
 $crc &= 0xffff;

 return $crc;
 }

------ Solution --------------------
Java >>> (0 shifted to the left) does not require special processing in php, you can directly>
At most (crc> 8) is translated into ($ crc> 8) & 0xff)

Java byte [] type, no corresponding php data type
You can get the internal code ord byte ($ buffer [$ I])
You can also enter the function $ buffer = array_values (unpack ('C', $ buffer ));
The array returned by unpack ('C', $ buffer) starts with subscript 1, so sort out array_values.
If you use a foreach loop or a for loop starts from 1, you do not need to sort it out.

Nothing else.

If you think there are still problems, please give several results of java running