Integer.MIN_VALUE

[Savio Mascarenhas]

What will be the result of attempting to complie & run the following code?
public class minval
{
public static void main(String args[])
{
System.out.println(Math.abs(Integer.MIN_VALUE));
}
}
(a)Causes a compilation error
(b)Causes no error and the value printed on the screen is less than zero.
(c)Causes no error and the value printed on the screen is one more than the Integer.MAX_VALUE
(d)Will throw a runtime exception due to overflow - Integer.MAX_VALUE is less in magnitude than Integer.MIN_VALUE.

The result is (b).
An absolute +ve value is displayed in the case of Byte.MIN_VALUE & Short.MIN_VALUE.Why not so in the case of an int.?How does it actually work ?

[peter waterhouse]

I believe that you get positive values from Byte_MIN and Short_MIN because there is no Math.abs function that takes a byte or a short as an argument. therefore when a byte or a short are passed in to the argument they are converted into an int.
the min value of a byte in 2's complement is: (binary) 1000000 = -128
so when this is converted to an int it is represented by:
0000 0000 0000 0000 0000 0000 1000 0000, and the one is no longer the highest bit (and is therefore not negative) and is therefore +128 instead of -128.

[Savio Mascarenhas]

Originally posted by peter waterhouse:
I believe that you get positive values from Byte_MIN and Short_MIN because there is no Math.abs function that takes a byte or a short as an argument. therefore when a byte or a short are passed in to the argument they are converted into an int.
the min value of a byte in 2's complement is: (binary) 1000000 = -128
so when this is converted to an int it is represented by:
0000 0000 0000 0000 0000 0000 1000 0000, and the one is no longer the highest bit (and is therefore not negative) and is therefore +128 instead of -128.

Peter,
What happens to Integer.MIN_VALUE ?Why does the negative sign still persist even after abs() ?

[peter waterhouse]

the Integer.MIN_VALUE is an absolute value in itself therefore it returns itself when you apply abs to it.
note that the same thing happens when you apply Long.MIN_VALUE
From the Docs:
Returns the absolute value of an int value. If the argument is not negative, the argument is returned. If the argument is negative, the negation of the argument is returned.
Note that if the argument is equal to the value of Integer.MIN_VALUE, the most negative representable int value, the result is that same value, which is negative.