The isPresent() method of java.util.Optional class in Java is used to find out if there is a value present in this Optional instance. If there is no value present in this Optional instance, then this method returns false, else true.
Syntax:
public boolean isPresent()
Parameters: This method do not accept any parameter.
Return value: This method returns a boolean value stating whether if there is a value present in this Optional instance.
Below programs illustrate isPresent() method:
Program 1:
// Java program to demonstrate// Optional.isPresent() 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);          // check for the value        System.out.println("Is any value present: "                           + op.isPresent());    }} |
Output:
Optional: Optional[9455] Is any value present: true
Program 2:
// Java program to demonstrate// Optional.isPresent() 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 {              // check for the value            System.out.println("Is any value present: "                               + op.isPresent());        }        catch (Exception e) {            System.out.println(e);        }    }} |
Output:
Optional: Optional.empty Is any value present: false
Reference: https://docs.oracle.com/javase/9/docs/api/java/util/Optional.html#isPresent–
