JAVAEE: JSP passes the value to the database, the test information is logged in dsjtftrhfjftyheg

JAVAEE: JSP passes the value to the database and logs in the test information

PersonDAO.java

package dao;

import java.sql.*;

import domain.Person;
import util.JDBCUtils;

/ **
 * A program in the data layer
 * Objects are returned in the DAO layer, and these objects can be added, deleted, modified and checked in the business layer
 * * /
public class PersonDAO {   

    public Person login(Person user) { //登录      
        Person existUser = null;
        Connection conn = null;
        PreparedStatement stmt = null;
        ResultSet rs = null;

        try {// JDBC query
            conn = JDBCUtils.getConnection ();
            String sql = "select * from person where name =? and password =?"; //
            Stmt = conn.prepareStatement (sql); // will sql when the database is compiled Send to database for compilation

            // Set the sql parameter
            stmt.setString (1, user.getName ()); // Incoming data value, will not be used as a keyword-to prevent injection
            stmt.setString (2, user.getPassword ());           
            rs = stmt .executeQuery (); // Execute sql

            // If the login is successful, there is only one record           
            if (rs.next ()) {
                existUser = new Person (); // The logged-in user
                existsUser.setID (rs.getString ("ID"));
                existUser.setName (rs .getString ("name"));
                existUser.setPassword (rs.getString ("password"));
                existUser.setBirthDate (rs.getDate ("birthday"));
            }
        } catch (Exception e) {
            e.printStackTrace () ;
        }
        System.out.println (user.getName ());
        System.out.println (user.getPassword ());
        try {
             System.out.println (rs.getString ("name"));
        } catch (Exception e) {
            // TODO: handle exception
            System.out.println("2");

        }

        return existUser;
    }
}

This is a test file Test

package dao;
import util.JDBCUtils;
import java.sql.*;

import domain.Person;

public class test {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
         Person existUser = null;
            Connection conn = null;
            PreparedStatement stmt = null;
            ResultSet rs = null;

            try {// JDBC query
                conn = JDBCUtils.getConnection ();
                String sql = "select * from person where name =? and password =?"; //
                Stmt = conn.prepareStatement (sql); // SQL Send to database for compilation

                // Set the sql parameter
                stmt.setString (1, "Tom"); // Incoming data value, will not be used as a keyword-to prevent injection
                stmt.setString (2, "12345");           
                rs = stmt.executeQuery () ; // Execute sql

                // If the login is successful, there is only one record           
                if (rs.next ()) {
                    existUser = new Person (); // The logged-in user
                    existsUser.setID (rs.getString ("ID"));
                    existUser.setName (rs .getString ("name"));
                    existUser.setPassword (rs.getString ("password"));
                    existUser.setBirthDate (rs.getDate ("birthday"));
                }
            } catch (Exception e) {
                e.printStackTrace () ;
            }
            try {
                System.out.println (rs.getString ("name"));
            } catch (Exception e) {
                // TODO: handle exception
            }
            System.out.println(existUser.getID());
            System.out.println(existUser.getName());
            System.out.println(existUser.getPassword());
            System.out.println(existUser.getBirthDate());
    }

}