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:
ramesh@gmail.com
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:
no value present
Note that we used the isPresent() method to check if there is a value inside the Optional object.
Related Optional Class Method Examples
- Create Optional Class Object in Java - empty(), of(), ofNullable() Methods
- Optional get() Method - Get Value from Optional Object in Java
- Optional isPresent() Method Example
- Optional orElse() Method Example
- Optional orElseGet() Method Example
- Optional orElseThrow() Method Example
- Optional filter() and map() Method Examples