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Q) what is the output of the fallowing program?




class order
{
       int oid;
       order (int oid)
       {
              oid=oid;
       }
       void displayorder()
       {
              System.out.println("order number :"+oid);
       }
}

class executeorder {

       public static void main(String[] args) {
              order o = new order(1001);
              o.displayorder();
       }

}
A)
Output:
order number :0

->the reason for the un expected output is the “name clash” between the instance variable and the parameter(local variable) of the constructor (i.e. oid).
->we can resolve the name clash by using “this” keyword.
Ex:

Order(int oid)
{
    This.oid=oid;
}
Output:
order number :1001

->”this” is a keyword in java which acts as an “implicit reference” to the current object.

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