In this source code example, we will demonstrate how to check a value is present in an Optional class object using the isPresent() method.
Optional isPresent() Method Example
The isPresent() method returns true if there is a value present, otherwise false.
In the below example, the isPresent() method returns true and prints the value:
import java.util.Optional; public class OptionalDemo { public static void main(String[] args) { String email = "ramesh@gmail.com"; Optional<String> stringOptional = Optional.ofNullable(email); if(stringOptional.isPresent()){ System.out.println(stringOptional.get()); }else{ System.out.println("no value present"); } } }
Output:
In the below example, the isPresent() method returns false and prints the message as "no value present":
import java.util.Optional; public class OptionalDemo { public static void main(String[] args) { String email = null; Optional<String> stringOptional = Optional.ofNullable(email); if(stringOptional.isPresent()){ System.out.println(stringOptional.get()); }else{ System.out.println("no value present"); } } }
Output:
Note that we used the isPresent() method to check if there is a value inside the Optional object.
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