Java Servlet插入到數據庫沒有getParameter（）;

Question

我正在嘗試編寫將數據插入數據庫（mysql）的servlet。問題是我需要將它寫入其他從servlet調用的類中，並在沒有getParameter（）的情況下插入數據; UPD：這裏是一個完整的代碼，我想壓縮成2班，1對servlet中，1類，它包含的參數

1. UserController.java

   protected void doPost(UserDao request, HttpServletResponse 
       response) throws ServletException, IOException { 
   
   
   
       UserDao.addUser(); 
   
   } 
   

2. UserDAO.java

   public class UserDao { 
   
       private static Connection connection; 
   
       public UserDao() { 
       connection = (Connection) DBconnect.getConnection(); 
       } 
   
   public static void addUser(String fname, String lname, String dob,  String email, String uid) { 
       try { 
   PreparedStatement preparedStatement = ((java.sql.Connection)  connection).prepareStatement("insert into users(firstname,lastname,dob,email) values (?, ?, ?, ?);"); 
       preparedStatement.setString(1, fname); 
   preparedStatement.setString(2, lname); 
   preparedStatement.setString(3, dob); 
   preparedStatement.setString(4, email); 
   preparedStatement.executeUpdate(); 
   
   } catch (SQLException e) { 
   e.printStackTrace(); 
   } 
       } 
   
   
   } 
   

Answer 1

從您的代碼我可以看到所有來自請求的參數現在設置爲使用r對象。

- >編寫一個接受User對象的DAO圖層類。然後編寫查詢以用用戶對象插入數據。

Answer 2

我不確定你在問什麼，所以我做了兩種不同的方式...... 希望這會給你一個足夠好的例子來做任何你想做的事情。

----使用用戶對象----

的servlet：

protected void doPost(HttpServletRequest request, HttpServletResponse 
response) throws ServletException, IOException { 

String fname = request.getParameter("firstName"); 
String lname = request.getParameter("lastName"); 
String dob = request.getParameter("dob"); 
String email = request.getParameter("email"); 
String uid = request.getParameter("userid"); 

dao.newUser(fname,lname,dob,email,uid); 

} 

userDAO的

public class UserDao { 

private Connection connection; 

public UserDao() { 
connection = DbConnect.getConnection(); 
    } 

public void newUser(String fname, String lname, String dob, String email, String uid){ 

    User user = new User(); 
    user.setFirstName(fname); 
    user.setLastName(lname); 
    user.setDob(dob); 
    user.setEmail(email); 

    addUser(user);} 

} 

    public void addUser(User user) { 
     try { 
    PreparedStatement preparedStatement = connection 
      .prepareStatement("insert into  
    users(firstname,lastname,dob,email) values (?, ?, ?, ?)"); 

    preparedStatement.setString(1, user.getFirstName()); 
    preparedStatement.setString(2, user.getLastName()); 
    preparedStatement.setString(3, user.getDob()); 
    preparedStatement.setString(4, user.getEmail()); 
    preparedStatement.executeUpdate(); 

} catch (SQLException e) { 
    e.printStackTrace(); 
} 
    } 


} 

----無需用戶OBJECT ----

的servlet：

protected void doPost(HttpServletRequest request, HttpServletResponse 
response) throws ServletException, IOException { 

String fname = request.getParameter("firstName"); 
String lname = request.getParameter("lastName"); 
String dob = request.getParameter("dob"); 
String email = request.getParameter("email"); 
String uid = request.getParameter("userid"); 

dao.addUser(fname,lname,dob,email,uid); 

} 

userDAO的

public class UserDao { 

private Connection connection; 

public UserDao() { 
connection = DbConnect.getConnection(); 
    } 

public void addUser(String fname, String lname, String dob, String email, String uid) { 
    try { 
PreparedStatement preparedStatement = connection 
     .prepareStatement("insert into users(firstname,lastname,dob,email) values (?, ?, ?, ?);"); 

preparedStatement.setString(1, fname); 
preparedStatement.setString(2, lname); 
preparedStatement.setString(3, dob); 
preparedStatement.setString(4, email); 
preparedStatement.executeUpdate(); 

} catch (SQLException e) { 
e.printStackTrace(); 
} 
} 


}