Java Enum

In java, we have a special type of class called enum, which is used to represent the set of constants.

The keywork enum is used to create an enum.

Syntax for creating enum

enum EnumName {
 // set of constants seperated by comma.
}

Example

enum Priority {
	LOW,
	MEDIUM,
	HIGH
}

The constant values should be always in uppercase.

In the above code, we have created an enum variable named Priority with constant value LOW,MEDIUM and HIGH.

To access the value of Priority enum we use the following code.

Priority level= Priority.MEDIUM;

Example program for Enum

enum Priority {
  LOW,
  MEDIUM,
  HIGH
}

public class Main {
  public static void main(String[] args) {
    Priority taskPriority = Priority.HIGH;
    System.out.println("Task Status:");
    
    switch(taskPriority) {
      case LOW:
        System.out.println("Task is of low priority.");
        break;
      case MEDIUM:
         System.out.println("Task is of medium priority");
        break;
      case HIGH:
        System.out.println("High priority task. Do it first");
        break;
    }
  }
}

Output

Task Status:
High priority task. Do it first

In the above program, we have created an enum with name Priority with set of values.

In the Main class, we have a enum variable of type Priority with the value Priority.HIGH.

Next, we check the values of it using switch statement and print the values accordingly.

Looping through Enum

It is also possible to loop through the enum values using values() method. Calling this function will return all the constant values of the enum.

Example to loop enum variable

enum Priority {
   LOW,
   MEDIUM,
   HIGH
}

public class Main
{
	public static void main(String[] args) {
		for (Priority level : Priority.values()) {
            System.out.println(level);
        }
	}
}

Output

LOW
MEDIUM
HIGH