Optional orElse() method in Java with examples

The orElse() method of java.util.Optional class in Java is used to get the value of this Optional instance, if present. If there is no value present in this Optional instance, then this method returns the specified value.

Syntax:

public T orElse(T value)

Parameters: This method accepts value as a parameter of type T to return if there is no value present in this Optional instance.

Return value: This method returns the value of this Optional instance, if present. If there is no value present in this Optional instance, then this method returns the specified value.

Below programs illustrate orElse() method:
Program 1:

// Java program to demonstrate
// Optional.orElse() method

import java.util.*;

public class GFG {

    public static void main(String[] args)
    {

        // create a Optional
        Optional<Integer> op
            = Optional.of(9455);

        // print value
        System.out.println("Optional: "
                           + op);

        // orElse value
        System.out.println("Value by orElse"
                           + "(100) method: "
                           + op.orElse(100));
    }
}

Output:

Optional: Optional[9455]
Value by orElse(100) method: 9455

Program 2:

// Java program to demonstrate
// Optional.orElse() method

import java.util.*;

public class GFG {

    public static void main(String[] args)
    {

        // create a Optional
        Optional<Integer> op
            = Optional.empty();

        // print value
        System.out.println("Optional: "
                           + op);

        try {

            // orElse value
            System.out.println("Value by orElse"
                               + "(100) method: "
                               + op.orElse(100));
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

Output:

Optional: Optional.empty
Value by orElse(100) method: 100

Reference: https://docs.oracle.com/javase/9/docs/api/java/util/Optional.html#orElse-T-