The boolean logical operators are : | , & , ^ , ! , || , && , == , != , ?:
| the OR operator
& the AND operator
^ the XOR operator
! the NOT operator
|| the short-circuit OR operator
&& the short-circuit AND operator
== the EQUAL TO operator
!= the NOT EQUAL TO operator
?: the IF-THEN-ELSE operator
These opearators act on boolean opearands according to this table
A B A|B A&B A^B !A false false false false false true true false true false true false false true true false true true true true true true false falseExample 1: the | , & , ^ , ! opearators
class Bool1{
public static void main(String args[]){
// these are boolean variables
boolean A = true;
boolean B = false;
System.out.println("A|B = "+(A|B));
System.out.println("A&B = "+(A&B));
System.out.println("!A = "+(!A));
System.out.println("A^B = "+(A^B));
System.out.println("(A|B)&A = "+((A|B)&A));
}
}
examine the output of this program using the table given
above.
Example 2: the || and && opearators
these are called short-circuit operators. If you examine the table given above, you notice that if either A or B is true then A|B is true. If you use the || operator instead of the | operator and if A is true then java will not evaluate B(assuming it is a expression). The same applies to the operation A&&B, if A is false then java will not evaluate B ( assuming it is a expression) and the result is false
class Bool2{
public static void main(String args[]){
int x = 0;
int y = 0;
boolean A = true;
boolean B = false;
// A is true , ++x<0 will not be evaluated since the || operator is used.
boolean C = A||(++x<0);
System.out.println("x = "+x);
System.out.println("C = "+C);
// ++y<0 will be evaluated since the | operator is used.
boolean D = A|(++y<0);
System.out.println("y = "+y);
System.out.println("D = "+D);
// note both C and D evaluate to true.
}
}
compile and run the above program. ++x is not evaluated since
A is true and we are using the || operator, however ++y is evaluated since
| is used.