Java中如何避免符号扩展位掩码？
我的位掩码是字节，我想保持它们原样，但我认为它们是符号扩展的。我不在乎该字节被视为正数还是负数，只要它具有相同的位集即可。我只花了几个小时调试我的代码，然后我发现我的字节位掩码只有在它们恰好为负数时才出现问题，花了一段时间才发现。我不可能是唯一一个对此有问题的人。有没有办法让一个字节表现得像无符号的一样？
My bit masks are bytes, and I'd like to keep them exactly as they are, but I think they're sign extended. I don't care if the byte is considered positive or negative, as long as it has the same bits set. I just spent a few hours debugging my code, and then I found I'm only having a problem with my byte bit masks when they happen to be negative, it took a while to find out. I can't be the only one who's had a problem with this. Is there a way to make a byte behave as if it was unsigned?
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如果您不希望在算术（或按位）运算符中使用字节时对其进行符号扩展，则需要显式地按位和 0xFF。它看起来有点难看，但如果你拥有的是字节，这是不可避免的（并且希望一个像样的 JIT 能够识别该习惯用法并从中生成有效的代码）。
If you don't want a byte to sign extend when you use it in arithmetic (or bitwise) operators, you need to explicitly bitwise-and it with 0xFF. It looks slightly ugly but is unavoidable if what you have is a
byte(and hopefully a decent JIT will be able to recognize the idiom and make efficient code out of it anyway).你的代码中有右移吗？你用“>>”吗而不是“>>”？有你的问题。
Do you have right-shift in your code? do you use '>>' instead of '>>>'? There is your problem.