Chapter 2, pg 75-76, switch statements (Java OCA 8 Programmer I Study Guide, Sybex)

[Tami Wakana]

For switch statements, I understand enum constants are allowed

private int getSortOrder(String firstName, final String lastName) {

String middleName = "Patricia";
final String suffix = "JR";
int id = 0;
switch(firstName) {
  case "Test":
     return 52;
  case middleName: // DOES NOT COMPILE
     id = 5;
     break;
  case suffix:
     id = 0;
     break;
  case lastName: // DOES NOT COMPILE
     id = 8;
     break;
  case 5: // DOES NOT COMPILE
     id = 7;
     break;
  case 'J': // DOES NOT COMPILE
     id = 10;
     break;
  case java.time.DayOfWeek.SUNDAY: // DOES NOT COMPILE
     id = 15;
     break;
  }
 return id;
}

I understand why they all don't compile. I'm wondering what an enum constant would look like (the last one doesn't compile because it is an enum value, not a constant)

[edited to fixed code tags]

[Ganesh Patekar]

Tami Wakana wrote:I'm wondering what an enum constant would look like (the last one doesn't compile because it is an enum value, not a constant)

Last one doesn't compile because cannot convert from enum DayOfWeek to String i.e. firstName means expecting String found enum
Here  java.time.DayOfWeek.SUNDAY is enum constant. They used fully qualified name of enum constant SUNDAY.

[Jeanne Boyarsky]

Tami,
Enums aren't in the OCA. You'll learn this for the OCP. But here's a preview:

This is an enum

enum Season {
  SPRING, SUMMER, FALL, WINTER;
}

And this is a switch statement that uses the enum

	public void method(Season s) {
		switch (s) {
		case SPRING:
			System.out.println("spring");
			break;
		case SUMMER:
			System.out.println("summer");
			break;
		case FALL:
			System.out.println("fall");
			break;
		case WINTER:
			System.out.println("winter");
			break;
		}
	}