Can You Create an Empty Java Enum with Methods?

Is it possible to create an empty Java enum type with methods?

In Java, an enum (short for enumeration) is a special data type that enables for a variable to be a set of predefined constants. While enums typically contain constants, they can also include methods, constructors, and even fields. However, one important consideration is whether an enum can be created without any predefined constants - essentially an 'empty' enum. Here's a detailed breakdown of how this works.

public enum EmptyEnum {
    ; // no constants defined 
    void someMethod() {
        System.out.println("This method belongs to an empty enum.");
    }
}

Causes

• Understanding that an enum with no constants is still valid Java syntax.
• Recognizing that enums in Java can contain methods and other member attributes.

Solutions

• Define an enum without constants, and add methods to it.
• You can instantiate it within other classes, or alongside the methods you want to implement.

Mistake: Assuming an enum cannot exist without constants.

Solution: Understand that enums can exist without constants and still hold method definitions.

Mistake: Not including a semicolon after the enum declaration.

Solution: Always include a semicolon after the enum declaration even if there are no constants.