1.32.15.When is v1 object in line 4 first subject to garbage collection?
import java.util.Vector;
public class MainClass { public static void main(String[] args) {
Vector v1 = new Vector();
Vector v2 = new Vector();
v1.add("A");
v1.add(v2);
String s = (String) v1.elementAt(0); // line 1
v1 = v2; // line 2
v2 = v1; // line 3
v1.add(s);
}
}