Two constructors in one class in Java

A class may include several constructors. The constructors' parameter lists, however, shouldn't be identical. Overloading of constructors is what this is called.

It is demonstrated by the following program:

ConstructorExpl.java

class ConstructorExpl1 {
   private int n1;
   public ConstructorExpl1() {
      n1 = 6;
   }
   public ConstructorExpl1(int n2) {
      n1 = n2;
   }
   public void display() {
      System.out.println("The number is: " + n1);
   }
}
public class ConstructorExpl {
   public static void main(String[] args) {
      ConstructorExpl1 o1 = new ConstructorExpl1();
      ConstructorExpl1 o2 = new ConstructorExpl1(15);
      o1.display();
      o2.display();
   }
}

Output:

Let's now examine the aforementioned software.

The data member num and the single member function display() that shows the value of num are the building blocks for the NumberValue class. The class NumberValue has two constructors, one of which accepts no parameters while the other of which accepts a single int parameter. The following code snippet illustrates this:

class ConstructorExpl1 {
   private int n1;
   public ConstructorExpl1() {
      n1 = 6;
   }
   public ConstructorExpl1(int n2) {
      n1 = n2;
   }
   public void display() {
      System.out.println("The number is: " + n1);
   }
}

The display() function is called on the objects o1 as well as o2 of the class ConstructorExpl that are created in the main() method. Here is a sample of code that illustrates this:

public class ConstructorExpl {
   public static void main(String[] args) {
      ConstructorExpl1 o1 = new ConstructorExpl1();
      ConstructorExpl1 o2 = new ConstructorExpl1(15);
      o1.display();
      o2.display();
   }
}

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