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Integer.Min_value

 
amit taneja
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hii
in one of the dan explaination to question...there is written that


If the argument is a negative integral value, then the returned value is the two's complement of the argument. The magnitude of Integer.MIN_VALUE is one greater than the magnitude of Integer.MAX_VALUE; therefore, the absolute value of Integer.MIN_VALUE exceeds the range of Integer.MAX_VALUE. Due to the limited range of type int, the two's complement of Integer.MIN_VALUE is Integer.MIN_VALUE. For that reason, the Math.abs method returns Integer.MIN_VALUE when the argument is Integer.MIN_VALUE. The negation of Short.MIN_VALUE is well within the range of type int; so Short.MIN_VALUE is never returned by the Math.abs method.


i m not able to understand fully what does that means...
if anybody pls explain me with eg. would be gr8 help to me...
 
marc weber
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The range of an int is -2^31 to (2^31)-1, which is -2147483648 to 2147483647. Note that the magnitude of the negative bound is one greater than that of the positive bound.

So the absolute value of Integer.MIN_VALUE is actually greater than Integer.MAX_VALUE. In particular, we might expect the absolute value to be +2147483648, but this is one greater than what can be expressed as a positive int, so this overflows to Integer.MIN_VALUE.

In terms of twos complement, flipping the bits of Integer.MIN_VALUE results in Integer.MAX_VALUE, then adding 1 causes the overflow. Note the output from the code below...

This is not a concern when a short is passed to the Math.abs(int) method, because the short is widened to type int, which can easily accomodate Short.MAX_VALUE + 1.
[ May 12, 2005: Message edited by: marc weber ]
 
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