Flow of Control - Java - page 116

Display 3.5 Truth Tables

AND

Exp_1 Exp_2 Exp_1 && Exp_2

true true true

true false false

false true false

NOT

false false false

Exp !(Exp)

true false

OR

false true

Exp_1 Exp_2 Exp_1 || Exp_2

true true true

true false true

false true true

false false false

A boolean variable, that is, one of type boolean , can be given the value of a Boolean
expression by using an assignment statement, in the same way that you use an assign-
ment statement to set the value of an int variable or any other type of variable. For
example, the following sets the value of the boolean variable isPositive to false :

boolean
variables in
assignments

int number = -5;
boolean isPositive;
isPositive = (number > 0);

If you prefer, you can combine the last two lines as follows:

boolean isPositive = (number > 0);

The parentheses are not needed, but they do make it a bit easier to read.
Once a boolean variable has a value, you can use the boolean variable just as you
would use any other Boolean expression. For example, the following code

boolean isPositive = (number > 0);
if (isPositive)
System.out.println("The number is positive.");
else
System.out.println("The number is negative or zero.");