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It is identical to the right-shift operator if the shifted value is positive. If it is negative the sign value can
change because the left-operand high-order bit is not retained and the sign value can change; Excerpt
from JLS:
"if n is negative, the result is equal to that of the expression (n>>s)(2<<~s) if the type of the left-hand operand is int, and to the result of the expression (n>>s)(2L<<~s) if the type of the left-hand operand is long. The added term (2<<~s) or (2L<<~s) cancels out the propagated sign bit. (Note that, because of the implicit masking of the right-hand operand of a shift operator, ~s as a shift distance is equivalent to 31-s when shifting an int value and to 63-s when shifting a longvalue.)"
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