Question

我正在尝试编写将数据插入数据库（mysql）的servlet。问题是我需要在从servlet调用的其他类中编写它，并在没有getParameter（）的情况下插入数据; UPD：这是一个完整的代码，我希望压缩成2个类，1个用于servlet，1个用于包含参数的类

UserController.java

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



    UserDao.addUser();

}

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

从您的代码中我可以看到请求中的所有参数现在都在User对象中设置。

- ＆GT;编写一个接受User对象的DAO图层类。然后编写查询以使用用户对象插入数据。

Answer 2

我不确定你究竟在问什么，所以我用两种不同的方式做到了...... 希望这会给你一个足够好的例子来做你想做的事情。

---- WITH USER OBJECT ----

<强>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);

}

<强> 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();
}
     }


}

----没有用户对象----

<强>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);

}

<强> 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();
}
 }


}

Java Servlet在没有getParameter（）的情况下插入数据库;

2 个答案: