我将如何匹配此 Java servlet 中数据库中的用户名和传递.JDBC 和 Servlet

Question

我正在尝试将我的HTML登录页面与数据库连接。我写了这个servlet，但在连接中遇到了一些错误。

String name=request.getParameter("uname");//Passing the HTML tag to he string
String psw= request.getParameter("psw");//
String QUERY="SELECT *FROM login WHERE EMAIL=?,PASS=?"; //Query 


Class.forName("com.mysql.jdbc.Driver");//Connection
try (Connection con = DriverManager.getConnection("jdbc:mysql://localhost/SmallERP", "root", "root")) {
PreparedStatement ps = con.prepareStatement(QUERY);
ps.setString(1, name);
ps.setString(2, psw);
try (ResultSet rs = ps.executeQuery()) {
if(rs.next()){
out.println("Done");
}else{
out.println("ERROR");
}
}
}

Answer 1

你必须在这里使用AND。修改后的查询：

String QUERY="SELECT * FROM login WHERE EMAIL=? And PASS=?";

我的完整例子是：-

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Scanner;
public class GetUserDetailsUsingPS {
public static void main(String[] args) throws ClassNotFoundException, SQLException {
// read user entered data
Scanner scanner = new Scanner(System.in);
System.out.println("Please enter email id:");
String id = scanner.nextLine();
System.out.println("User id=" + id);
System.out.println("Please enter password to get details:");
String pwd = scanner.nextLine();
System.out.println("User password=" + pwd);
printUserData(id, pwd);
}
private static void printUserData(String id, String pwd) throws ClassNotFoundException,
SQLException {
Connection con = null;
PreparedStatement ps = null;
ResultSet rs = null;
String query = "select name, country, password from Users where email = ? and password = ?";
try {
con = DBConnection.getConnection();
ps = con.prepareStatement(query);
//set the parameter
ps.setString(1, id);
ps.setString(2, pwd);
rs = ps.executeQuery();
while (rs.next()) {
System.out.println("Name=" + rs.getString("name") + ",country="
+ rs.getString("country") + ",password="
+ rs.getString("password"));
}
} finally {
if (rs != null)
rs.close();
ps.close();
con.close();
}
}
}