Logical Operators in Java

These operators are used to perform logical “AND”, “OR” and “NOT” operation, i.e. the function similar to AND gate and OR gate in digital electronics. They are used to combine two or more conditions/constraints or to complement the evaluation of the original condition under particular consideration. One thing to keep in mind is the second condition is not evaluated if the first one is false, i.e. it has a short-circuiting effect. Used extensively to test for several conditions for making a decision. Let’s look at each of the logical operators in a detailed manner: 

• ‘Logical AND’ Operator(&&): This operator returns true when both the conditions under consideration are satisfied or are true. If even one of the two yields false, the operator results false. For example, cond1 && cond2 returns true when both cond1 and cond2 are true (i.e. non-zero).

 
        Syntax: 
         

         condition1 && condition2
 

 

•  'Logical OR' Operator(||): This operator returns true when one of the two conditions under consideration are satisfied or are true. If even one of the two yields true, the operator results true. To make the result false, both the constraints need to return false.

        Syntax:

          condition1 || condition2

 

•  'Logical NOT' Operator(!): Unlike the previous two, this is a unary operator and returns true when the condition under consideration is not satisfied or is a false condition. Basically, if the condition is false, the operation returns true and when the condition is true, the operation returns false.

        Syntax:

        !(condition)