JAVAEE：JSP传值给数据库，测试信息进行登录dsjtftrhfjftyheg

JAVAEE：JSP传值给数据库，测试信息进行登录

PersonDAO.java

package dao;

import java.sql.*;

import domain.Person;
import util.JDBCUtils;

/**
 * 数据层一个程序
 * DAO层返回对象，在业务层通过操作这些对象来实现增删改查
 * */
public class PersonDAO {   

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

        try {//JDBC查询
            conn = JDBCUtils.getConnection();
            String sql = "select * from person where name=? and password=?"; //数据库编译时
            stmt = conn.prepareStatement(sql);  //将sql发送给数据库进行编译

            //设置sql参数
            stmt.setString(1,user.getName());   //传入数据值，不会作为关键字 --防止注入
            stmt.setString(2,user.getPassword());           
            rs = stmt.executeQuery();           //执行sql

            //如果登陆成功，只有一条记录           
            if (rs.next()) {
                existUser=new Person();     //表示已登录用户
                existUser.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;
    }
}

这个是个测试文件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查询
                conn = JDBCUtils.getConnection();
                String sql = "select * from person where name=? and password=?"; //数据库编译时
                stmt = conn.prepareStatement(sql);  //将sql发送给数据库进行编译

                //设置sql参数
                stmt.setString(1, "Tom");   //传入数据值，不会作为关键字 --防止注入
                stmt.setString(2, "12345");           
                rs = stmt.executeQuery();           //执行sql

                //如果登陆成功，只有一条记录           
                if (rs.next()) {
                    existUser=new Person();     //表示已登录用户
                    existUser.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());
    }

}