Logical Operators in Java
In this lesson, we will learn what is the Logical Operators and how it works in Java programming with some examples.
What is Logical Operators
Logical operators in Java are used to check if given conditions are true or false. They allow a program to make decisions based on multiple conditions. If the result of the logical operation is true, then 1 is returned; otherwise, 0 is returned.
There are 3 types of logical operators in Java and they are:
- AND (&&) Operator
- OR (||) Operator
- NOT (!) Operator
Now let's see the examples of all the logical operators one by one for more understanding.
AND && Operator
The AND (&&) operator is used to check if two or more given conditions are true or not. The output of AND (&&) operator is 1 (true) only if all the given conditions are correct otherwise the output will be 0 (false) if any one of the given conditions is wrong.
int x=15, y=2, z=6, k=25, a, b;
a = x>5 && y<6 && k>=25; // output of a is 1
b = x>y && k<25; // output of b is 0
In the example above the output of a is 1 because all the three given conditions x>5, y<6 and k>=25 are correct (true). On the other hand the output of b is 0 because out of the two given conditions x>y and k<25 the second condition k<25 is wrong (false).
OR || Operator
The OR (||) operator is used to check if any one of the given conditions is true or not. The output of OR (||) operator is 1 (true) if at least any one of the given conditions is correct otherwise the output will be 0 (false) only if all the given conditions are wrong.
int x=15, y=2, z=6, k=25, a, b;
a = x<5 || y<6 || k>=25; // output of a is 1
b = x<y || k<25; // output of b is 0
In the example above the output of a is 1 because out of the three given conditions x<5, y<6 and k>=25 the second condition is correct (true). On the other hand the output of b is 0 because out of the two given conditions x<y and k<25 both of them are wrong (false).
NOT ! Operator
The NOT (!) operator reverse the value of the condition. If the condition is false then the output of NOT (!) operator becomes true (1). If the condition is true then the output becomes false (0).
int x=15, y=10, a, b;
a = !(x>5); // output of a is 0
b = !(y<5); // output of b is 1
In the example above the output of a is 0 because the given condition x>5 is correct (true) so ! (NOT) operator changed the output from 1 to 0. On the other hand the output of b is 1 because the given condition y<5 is wrong (false) so ! (NOT) operator changed the output from 0 to 1.
Test Your Knowledge
Attempt the questions in the exercise to check whether you have understood the lesson clearly.