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Q) What is constructor chaining?




A)
->from within one constructor of a class calling another constructor of the same class(object) is known as constructor chaining.
-> ”this”  keyword is used to implement constructor chaining.
//constructor chaining
class employees
{
       int empno;
       employees()
       {
              System.out.println("one employee appointed");
       }
       employees(int eno)
       {
              this(); //constructor chaining
              empno=eno;
       }
       void display()
       {
              System.out.println("epno :"+empno);
       }
}

class constructorchaining {

       public static void main(String[] args) {
              employees e = new employees(1001);
              e.display();

       }

}

Output :
one employee appointed
epno :1001

->the purpose of constructor chaining is at the time of object creation only one constructor is executed. But at that time we want to call 2 or more constructors this constructor chaining is used with the help of “this” keyword.

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