import java.util.Vector;

/*
 *  Example of clear() method 
 */
public class VectorExample
{

    public static void main( String[] args )
    {
        Vector<Integer> vector = new Vector<>();

        vector.add(10);
        vector.add(20);
        vector.add(30);

        System.out.println("vector  : " + vector + "\n");

        /*
         * Removes all of the elements from this Vector. The Vector will be
         * empty after this call returns (unless it throws an exception).
         */
        vector.clear();

        System.out.println("vector  : " + vector + "\n");

    }
}

Output