Return Types in Java

What is a Return Type?

A return type is the data type of the value that a method sends back to the calling method.

Syntax

returnType methodName(parameters) {
    // code
    return value;
}

• returnType → int, double, String, boolean, etc.
• return value; → sends result back

Example 1: Returning an Integer

public class Example1 {

    public static void main(String[] args) {
        Example1 obj = new Example1();

        int result = obj.add(10, 5);
        System.out.println("Result = " + result);
    }

    int add(int a, int b) {
        return a + b;
    }
}

Output

Here:

• Return type = int
• Method returns an integer value

Flow of execution

1. main() method starts execution
2. Object obj is created
3. add(10, 5) method is called
4. Inside method → a + b is calculated
5. Value 15 is returned to main()
6. Stored in result and printed

Example 2: Returning a String

public class Example2 {

    public static void main(String[] args) {
        Example2 obj = new Example2();

        String message = obj.greet("Harini");
        System.out.println(message);
    }

    String greet(String name) {
        return "Hello " + name;
    }
}

Output

Flow of execution

1. main() starts
2. Object is created
3. greet("Harini") is called
4. Method creates "Hello Harini"
5. Returns string to main()
6. Printed on screen

Example 3: Returning a Boolean

public class Example3 {

    public static void main(String[] args) {
        Example3 obj = new Example3();

        boolean result = obj.isEven(4);
        System.out.println("Is Even? " + result);
    }

    boolean isEven(int number) {
        return number % 2 == 0;
    }


}

Output

Flow of execution

1. main() starts
2. Object is created
3. isEven(4) is called
4. Condition 4 % 2 == 0 checked
5. Returns true
6. Printed as result

Example 4: void Return Type

public class Example4 {

     public static void main(String[] args) {
        Example4 obj = new Example4();

        obj.display();   // calling method
    }

    void display() {
        System.out.println("Hello");
    }


}

Output

Flow of execution

1. main() starts
2. Object is created
3. display() is called
4. Method directly prints "Hello"
5. No value returned