The get() method of java.util.Optional class in Java is used to get the value of this Optional instance. If there is no value present in this Optional instance, then this method throws NullPointerException.
Syntax:
public T get()
Parameters: This method do not accept any parameter.
Return value: This method returns the value of this instance of the Optional class.
Exception: This method throws NoSuchElementExcpetion if there is no value present in this Optional instance.
Below programs illustrate get() method:
Program 1:
// Java program to demonstrate// Optional.get() 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); // get the value System.out.println("Value of this Optional: " + op.get()); }} |
Output:
Optional: Optional[9455] Value of this Optional: 9455
Program 2:
// Java program to demonstrate// Optional.get() 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 { // get the value System.out.println("Value of " + "this Optional: " + op.get()); } catch (Exception e) { System.out.println(e); } }} |
Output:
Optional: Optional.empty java.util.NoSuchElementException: No value present
Reference: https://docs.oracle.com/javase/9/docs/api/java/util/Optional.html#get–
