java - jsp中有关使用准备好的语句进行mysql更新的异常

Question

java.sql.SQLException:参数索引超出范围(1 > 参数数量，为 0)。

我正在尝试使用jsp进行动态Web项目，当我尝试使用PreparedStatment对象更新mysql数据库时，我遇到了这个异常，我在很多线程中读到这意味着你没有使用正确的引用“？”的索引，但我认为这不是我的情况，我希望这不是一个愚蠢的问题，但我只是找不到我的错误。

这是代码:

package classes;

import java.sql.DriverManager;
import java.sql.SQLException;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.PreparedStatement;

public class DataUser {
    private String username;
    private String name;
    private String surname;
    private String email;
    private String wallet;
    private String password;
    private String coin;
    private Connection conexion;
    private PreparedStatement preparedSt;   
    public DataUser(String username, String name, String surname, String email, String wallet, String password, String coin) throws ClassNotFoundException{

        this.username = username;
        this.name = name;
        this.surname = surname;
        this.email = email;
        this.wallet = wallet;
        this.password = password;
        this.coin = coin;

        Class.forName("com.mysql.jdbc.Driver");

        try {
            this.conexion = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/pruebajsp", "root", "");
            this.preparedSt = (PreparedStatement) conexion.prepareStatement("INSERT INTO USERS (USERNAME, NAME, SURNAME, EMAIL, WALLET, PASSWORD, INVESTMENT_COIN) VALUES ('?', '?', '?', '?', '?', '?', '?')");
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSurname() {
        return surname;
    }

    public void setSurname(String surname) {
        this.surname = surname;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getWallet() {
        return wallet;
    }

    public void setWallet(String wallet) {
        this.wallet = wallet;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getCoin() {
        return coin;
    }

    public void setCoin(String coin) {
        this.coin = coin;
    }

    @Override
    public String toString() {
        return "DataUser [username=" + username + ", name=" + name + ", surname=" + surname + ", email=" + email
                + ", wallet=" + wallet + ", password=" + password + ", coin=" + coin + "]";
    }




    public void updateDB(){
        try{
            this.preparedSt.setString(1, this.username);
            this.preparedSt.setString(2, this.name);
            this.preparedSt.setString(3, this.surname);
            this.preparedSt.setString(4, this.email);
            this.preparedSt.setString(5, this.wallet);
            this.preparedSt.setString(6, this.password);
            this.preparedSt.setString(7, this.coin);
            this.preparedSt.executeUpdate();
        }catch(SQLException e){
            e.printStackTrace();  
        }
    }

}

我在jsp文件中所做的是:

<%
    DataUser user = new DataUser(request.getParameter("username"), request.getParameter("name"), request.getParameter("surname"),
            request.getParameter("email"), request.getParameter("wallet"), request.getParameter("password"),
            request.getParameter("coin"));
    user.updateDB();
%>

提前谢谢您。

Answer 1

values (?, ?, ?, ...)

占位符周围没有单引号。否则，它们是文字字符串。