Hi Friend,

Use Switch-Case in your program like the following:

import java.util.*;

class addproduct{
addproduct(){
System.out.println("I am the class addproduct");
}
}

class updateproduct{
updateproduct(){
System.out.println("I am the class updateproduct");
}
}

class deleteproduct{
deleteproduct(){
System.out.println("I am the class deleteproduct");
}
}

class viewproduct{
viewproduct(){
System.out.println("I am the class viewproduct");
}
}



public class productmain{
public static void main(String[] args) throws Exception {
Scanner scan = new Scanner(System.in);
int menu = 0;
System.out.println("Test");
System.out.println();
System.out.println("1. Add Product");
System.out.println("2. Update Product");
System.out.println("3. Delete Product");
System.out.println("4. View Product");
System.out.println("5. Exit");

boolean quit = false;
do{
System.out.print("Please enter your choice: ");
menu = scan.nextInt();
System.out.println();
switch(menu) {
case 1:
addproduct add=new addproduct();
break;
case 2:
updateproduct update=new updateproduct();
break;
case 3:
deleteproduct delete=new deleteproduct();
break;
case 4:
viewproduct view=new viewproduct();
break;
case 5:
quit = true;
break;
default:
System.out.println("Invalid Entry!");
}
}
while (!quit);
}
}

Thanks