Optional ofNullable() method in Java with examples
Last Updated :
30 Jul, 2019
Improve
The ofNullable() method of java.util.Optional class in Java is used to get an instance of this Optional class with the specified value of the specified type. If the specified value is null, then this method returns an empty instance of the Optional class.
Syntax:
Java
Java
public static <T> Optional<T> ofNullable(T value)Parameters: This method accepts value as parameter of type T to create an Optional instance with this value. It can be null. Return value: This method returns an instance of this Optional class with the specified value of the specified type. If the specified value is null, then this method returns an empty instance of the Optional class. Below programs illustrate ofNullable() method: Program 1:
// Java program to demonstrate
// Optional.ofNullable() method
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// create a Optional
Optional<Integer> op1
= Optional.ofNullable(9455);
// print value
System.out.println("Optional 1: "
+ op1);
}
}
Output:
Program 2:
Optional 1: Optional[9455]
// Java program to demonstrate
// Optional.ofNullable() method
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// create a Optional
Optional<String> op2
= Optional.ofNullable(null);
// print value
System.out.println("Optional 2: "
+ op2);
}
}
Output:
Reference: https://docs.oracle.com/javase/9/docs/api/java/util/Optional.html#ofNullable-T-
Optional 2: Optional.empty