shift question

[dlc]

hi all,
i do'nt know what differences between Sample1 & Sample2.
code 1:
class Sample1{
public static void main(String args[]){
int i=-1;
i=i<<-2;
System.out.println(i);
}
}
code 2:
class Sample2{
public static void main(String args[]){
int i=-1;
i=i<<2;
System.out.println(i);
}
}
thank you!!

[Igor Ko]

try it, it will help:

class Sample3{
public static void main(String args[]){
   int i=-1;
   System.out.println(Integer.toBinaryString(i));
   System.out.println(Integer.toBinaryString(i<<3));
   System.out.println(Integer.toBinaryString(i<<-3));
}

If the promoted type of the left-hand operand is int, only the five lowest-order bits of the right-hand operand are used as the shift distance. It is as if the right-hand operand were subjected to a bitwise logical AND operator & (�15.22.1) with the mask value 0x1f. The shift distance actually used is therefore always in the range 0 to 31, inclusive.

Java Language Specification.
So actually:
shfit -1 is shift to 31
shift -2 is shift to 30
shift -3 is shift to 29
shift -4 is shift to 28
. . . . . . . . . . . . .
[ March 15, 2004: Message edited by: Igor Ko ]

[Dirk Schreckmann]

dlc,
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