A constructor of a class can be called from another constructor of the same class. The constructor calling statement (this()) should be the first statement in the constructor. Review the code below.

Java Code:
public class ClassA {

	public ClassA(){
		this(2);
		System.out.println("Constructor without parameter.");
	}
	
        public ClassA(int a){
		System.out.println("Constructor with int parameter: " + a);
	}

        public static void main(String[] str)
       {
       ClassA obj = new ClassA();
       }
}
Output:

Java Code:
Constructor with int parameter: 2
Constructor without parameter.