Enums

An Enum (Enumeration) is a special "class" that represents a group of constants (unchangeable variables, like final variables).

Declaring an Enum

enum Level {
  LOW,
  MEDIUM,
  HIGH
}

Using an Enum

Level myVar = Level.MEDIUM;

Enum in Switch Statement

Enums are often used in switch statements to check for corresponding values.

switch(myVar) {
  case LOW:
    System.out.println("Low level");
    break;
  case MEDIUM:
     System.out.println("Medium level");
    break;
  case HIGH:
    System.out.println("High level");
    break;
}

Loop Through an Enum

Enums have a values() method.

for (Level l : Level.values()) {
  System.out.println(l);
}

Interactive Code

Enums can have fields and methods too!

Quiz

Next Steps

Now that we are mastering data types, let's learn how to persist data with File I/O.