2. Write a Java program to create a vector, add elements at the end, at specified location onto the vector and display the elements. Write an option driven program using switch…case.

import java.util.*;

import java.io.*;

import java.lang.String;

class VectorPro

{

    public static void main(String args[])

    {

        try

        {

       

            int length = args.length;

            int i,ch;

            String str1,str2;

            Vector list = new Vector();

            for( i=0;i<length;i++)

            {

                list.addElement(args[i]);

            }

            DataInputStream in= new DataInputStream(System.in);

           

            for(;;)

            {

                System.out.println("1.Add element at end");

                System.out.println("2.Add element at specific location");

                System.out.println("3.Display");

                System.out.println("4.Exit");       

                System.out.println("Enter your choice:");

   

                str1=in.readLine();

                ch=Integer.parseInt(str1);

                switch(ch)

                {

                   

             case 1: System.out.print("Enter an element to insert at end:");

                            str2=in.readLine();

                            list.addElement(str2);

                            length++;   

                            break;

                       

             case 2: System.out.print("Enter an element & position:");

                            str1=in.readLine();

                            str2=in.readLine();

                            int pos;

                            pos=Integer.parseInt(str2);

                            if(pos<=length && pos>0)

                            {

                                list.insertElementAt(str1,pos-1);

                                length++;

                                break;

                            }

                            else

                            {

                                System.out.println("Invalid Position!");

                            }

                   

            case 3:

                            System.out.println("List of elements:");

                            for(i=0;i<length;i++)

                            System.out.println(list.elementAt(i));

                            break;

                   

            default:       System.exit(0);

   

                }

                              

            }

        }

        catch(Exception e){}

    }

}