Create Optional Class Object in Java - empty(), of(), ofNullable() Methods

In this source code example, we will demonstrate the different ways to create Optional class objects in Java.

The Optional class introduced in Java 8 to avoid null checks and NullPointerException.

The Optional class provides empty(), of(), ofNullable() methods to create it's objects.

Create Optional Class Object in Java - empty(), of(), ofNullable() Methods

There are several ways of creating Optional objects.

empty() Method

To create an empty Optional object, we simply need to use its empty() static method:
 Optional<Object> emptyOptional = Optional.empty();

of() Method

The of() static method returns an Optional with the specified present non-null value.

 Optional<String> emailOptional = Optional.of("ramesh@gmail.com");

ofNullable() Method

The ofNullable() static method returns an Optional describing the specified value, if non-null, otherwise returns an empty Optional.
 Optional<String> stringOptional = Optional.ofNullable("ramesh@gmail.com");

Here is the complete example with output:

import java.util.Optional; public class OptionalDemo { public static void main(String[] args) { String email = "ramesh@gmail.com"; // of, empty, ofNullable Optional<Object> emptyOptional = Optional.empty(); System.out.println(emptyOptional); Optional<String> emailOptional = Optional.of(email); System.out.println(emailOptional); Optional<String> stringOptional = Optional.ofNullable(email); System.out.println(stringOptional); } }

Output:

Optional.empty Optional[ramesh@gmail.com] Optional[ramesh@gmail.com]

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