<snippet>
if (i < in.length) val |= ((int)in[i++] & 0xFF) << 8;
if (i < in.length) val |= ((int)in[i++] & 0xFF);
</snippet>Couldn't that simply be:
<snippet>
if (i < in.length) val |= ((int)in[i++]) << 8;
if (i < in.length) val |= ((int)in[i++]);
</snippet>My only thought is that an integer is 32 bits in Java, so it would mask everything but the lowest byte? We go from 1 byte, to an integer, then we pull the lowest byte?
Example (in pseudocode. 0b is my prefix for binary, ok?):
<snippet>
in[x] = 0b11101110 castedX = (int) in[x]
// castedX is now == 00000000 00000000 00000000 11101110 maskedCastedX = castedX & 0b11111111
// maskedCastedX is now == 00000000 00000000 00000000 11101110
</snippet>Now, it seems to me that the mask didn't do anything. The mast is internally cast up to an integer, making it equal to
00000000 00000000 00000000 11111111
However, since we cast a byte up to an integer, the high word and the high byte of the low word are going to be 0 anyways, so no information lost or changed by the mask. Am I going crazy?
It seems to me that the shift would come out the same way if we ommitted the mask. No sense making it hard to read and taking extra CPU cycles. The mask seems to do nothing, because you should get the same result even if you remove it altogether. It may be something to do with operator precendence, but I don't think so...
Excuse me if I made any mistakes. As I said, bitwise operations are *not* my strong point. If I *am* wrong, please explain why, so that I don't get stuck elsewhere. (Ian: That's why I was asking you about Bas64. It's not the concept, it's the bitwise operations that I suck at and I have to do them out on paper or something before I understand them.)
Aeloria
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