How valueOf(String) method of enum works ?

valueOf(String) method of enum

Enum.valueOf(String) method of enum used to convert a String into enum.

If you pass any invalid enum value, it will throw exception :

java.lang. IllegalArgumentException: No enum const class

enum Day {

       SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY;

}

public class EnumTest {

       public static void main(String[] args) {

              Day day1 = Day.valueOf(“MONDAY”);

              System.out.println(day1);

              Day day2 = Day.valueOf(“sunday”);

              System.out.println(day2);

       }

}

Output

MONDAY

Exception in thread "main" java.lang.IllegalArgumentException: No enum constant Day.sunday