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Switch (ing) enum (s) in java

Java 1.5 enums are a life saver. There is a small gotcha in thier use especially in a switch statement(More so for a guy coming from hard core 1.4).

When creating an enum reference - you would need to Qualify with enum Type. However, The case labels while switch(ing) on an enum variable will only take enum constant of the *SAME* enum type. And ONLY the constant name. It SHOULD not be QUALIFIED.

Ex: In the following code, The second case label gives a compilation error.

public class EnumTest {

 enum WeekDays {SUN, MON, TUE, WED, THU, FRI, SAT};

 public static void main(String arg[]) {
  WeekDays r = WeekDays.SUN;
  switch (r) {
  case SUN:
   break;
  case WeekDays.MON:
   break;
  default:
   break;
  }
 }
}

There are good advantages here. For one, Refactoring doesnot involve lot of changes. Maintains Typesafety. It avoids a possibility of human error where you are comparing Fruit enums and Vegitable enums. Because they are different :)

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