Firstly, you can not shift a byte in java, you can only shift an int or a long. So the byte will undergo promotion first, e.g.
00101011 -> 00000000000000000000000000101011
or
11010100 -> 11111111111111111111111111010100
Now, x >> N means (if you view it as a string of binary digits):
- The rightmost N bits are discarded
- The leftmost bit is replicated as many times as necessary to pad the result to the original size (32 or 64 bits), e.g.
00000000000000000000000000101011 >> 2 -> 00000000000000000000000000001010
11111111111111111111111111010100 >> 2 -> 11111111111111111111111111110101