valueOf method of enum

Enum valueOf() is a static method which takes a string argument and can be used to convert a String into enum.

valueOf(String) method of enum will throw "Exception in thread "main" java.lang. IllegalArgumentException: No enum const class" if you supply any string other than enum values.

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("tuesday");

            System.out.println(day2);

      }

}

Output:

MONDAY

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

      at java.lang.Enum.valueOf(Unknown Source)

      at Day.valueOf(EnumTest.java:1)

      at EnumTest.main(EnumTest.java:12)