Я получаю эту ошибку The server encountered an unexpected condition that prevented it from fulfilling the request. java.lang.NullPointerException.Я пытаюсь вставить данные в базу данных MySQL.Я создал динамический веб-проект, и в файле index.jsp у меня есть форма.Также я следую архитектуре MVC.
Это ошибка, которую я получаю
CustomerController.java servelet
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//doGet(request, response);
//Get the data
String name = request.getParameter("name");
String email = request.getParameter("email");
String address = request.getParameter("address");
String sex = request.getParameter("sex");
String bday = request.getParameter("bday");
String tel = request.getParameter("tele");
String password= request.getParameter("password");
//Setup an Employee object
Customer customer = new Customer();
customer.setName(name);
customer.setEmail(email);
customer.setAddress(address);
customer.setSex(sex);
customer.setBday(bday);
customer.setTelephone(tel);
customer.setPassword(password);
//Setup am EmpAddQuery object
CustomerAddQuery obj = new CustomerAddQuery();
//Pass the Employee to EmpAddQuery to add to the database
obj.addData(customer); //line 69
//Pass execution control to the ReadServlet
String url = "/index.jsp";
RequestDispatcher dispatcher = request.getRequestDispatcher(url);
dispatcher.forward(request, response);
}
Я только скопировалdoPost метод сервлета
CustomerAddQuery.java
package dbhelpers;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
import models.Customer;
public class CustomerAddQuery {
DBConnection databaseCon = new DBConnection();
public void addData(Customer customer)
{
String query = "insert into customers (`name`, `email`, `address`,
`sex`, `bday`, `telephone` , `password`) values (?,?,?,?,?,?,?)" ;
try {
Connection con = databaseCon.dbconnect();
PreparedStatement pst = con.prepareStatement(query); //line 27
pst.setString(1, customer.getName());
pst.setString(2, customer.getEmail());
pst.setString(3, customer.getAddress());
pst.setString(4, customer.getSex());
pst.setString(5, customer.getBday());
pst.setString(6, customer.getTelephone());
pst.setString(7, customer.getPassword());
pst.execute();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
DBConnect.java file
package dbhelpers;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBConnection {
public static Connection dbconnect(){
Connection con = null;
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost/vehicle_rental_system", "root", "");
}
catch (ClassNotFoundException | SQLException e){
System.out.println(e);
}
return con;
}
}