Question

What is the output of this program?
import java.util.*;
class vector
{
public static void main(String args[])
{
Vector obj = new Vector(4,2);
obj.addElement(new Integer(3));
obj.addElement(new Integer (2));
obj.addElement(new Integer(5));
obj.removeAll(obj);
System.out.println(obj.isEmpty());
}
}​

Answer 1

Output.

>> true

Explanation.

Given co‎de -

import java.util.*;

class vector{

   public static void main(String args[]){

       Vector obj = new Vector(4,2);

       obj.addElement(new Integer(3));

       obj.addElement(new Integer (2));

       obj.addElement(new Integer(5));  

       obj.removeAll(obj);

       System.out.println(obj.isEmpty());

   }

}

⊕ Here, an array of three elements - 3, 2 and 5 is created.

⊕ The removeAll() method removes all the elements present in the vector.

⊕ So, the vector object becomes empty.

⊕ The isEmpty() method checks whether the vector is empty or not. Yes, it is empty. So, it returns true.

See attachment for verification.