content: public class JDBCCalls {
  
      public static void main(String[] args) {
          int option = Integer.parseInt(args[0]);
          DAOClass dao = new DAOClass();
  
          switch (option) {
          case 1:
              int rollno = Integer.parseInt(args[1]);
              String name = args[2];
              String grade = args[3];
              String dob = args[4];
              int fee = Integer.parseInt(args[5]);
  
              if (dao.insert(rollno, name, grade, dob, fee))
                  System.out.println("Inserted successfully");
              else
                  System.out.println("Insertion error");
              break;
  
          case 2:
              rollno = Integer.parseInt(args[1]);
  
              if (dao.delete(rollno))
                  System.out.println("Deleted successfully");
              else
                  System.out.println("Deletion error");
  
              break;
  
          case 3:
              rollno = Integer.parseInt(args[1]);
              fee = Integer.parseInt(args[2]);
  
              if (dao.modify(rollno, fee))
                  System.out.println("Modified successfully");
              else
                  System.out.println("Modification error");
              break;
  
          case 4:
              try {
                  rollno = Integer.parseInt(args[1]);
                  dao.display(rollno);
                  break;
              } catch (Exception e) {
                  dao.display();
                  break;
              }
          }
  
      }
  
  }
  