How to Create Custom Constructor Enum in Java

In this example, we will  show a custom constructor in an enumeration with private definition.

Source Code

1.enum)

package com.beginner.examples;

public enum Week {

	MON(1), TUE(2), WED(3), THRUS(4), FIR(5), STA(6), SUN(7);

	private int num;

	// The default constructor in the enumeration is private,
	// and defining a public constructor will cause an error

	private Week(int num) {
		this.num = num;
	}

	@Override
	// Override the toString() method in order to be able to return the attribute
	// value num
	public String toString() {

		return this.name() + " : " + this.num;
	}

}

2)

package com.beginner.examples;

public class EnumCustomConstructor {

	public static void main(String[] args) {

		// Use custom enumerations
		Week w1 = Week.MON;

		Week w2 = Week.TUE;

		Week w3 = Week.WED;

		
		System.out.println(w1);
		System.out.println(w2);
		System.out.println(w3);

	}

}

Output:

MON : 1
TUE : 2
WED : 3