Java-Web前后端交互实现登陆注册（附源码）

1.完成用户登录功能。

2.完成注册功能。

3.主体利用Maven导入java中的jar包，使用Servlet实现前后端交互，使用mybatis以及注解，Mysql进行数据保存，Tomcat服务器进行开发。

效果图

项目结构

代码

1. mapper(相对应注解)

package com.itheima.mapper;import com.itheima.pojo.User;import org.apache.ibatis.annotations.Insert;import org.apache.ibatis.annotations.Param;import org.apache.ibatis.annotations.Select;public interface UserMapper {        @Select("select * from tb_user where username=#{username} and passWord = #{password}")    User select(@Param("username") String username, @Param("password")String password);        @Select("select * from tb_user where username=#{username}")    User selectByUsername(String usernmae);        @Insert("insert into tb_user values(null,#{username},#{password})")    void add(User user);}

2. pojo(实体类)

package com.itheima.pojo;public class User {    private Integer id;    private String username;    private String password;    public Integer getId() {        return id;    }    public void setId(Integer id) {        this.id = id;    }    public String getUsername() {        return username;    }    public void setUsername(String username) {        this.username = username;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    @Override    public String toString() {        return "User{" +                "id=" + id +                ", username='" + username + '\'' +                ", password='" + password + '\'' +                '}';    }}

3.util(工具类)

package com.itheima.util;import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.sqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder;import java.io.IOException;import java.io.InputStream;public class SqlSessionFactoryUtils {    private static SqlSessionFactory sqlSessionFactory;    static {        String resource = "mybatis-config.xml";        InputStream inputStream = null;        try {            inputStream = Resources.getResourceAsStream(resource);        } catch (IOException e) {            e.printStackTrace();        }        sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);    }    public static SqlSessionFactory getSqlSessionFactory() {        return sqlSessionFactory;    }}

4.WEB（Servlet）

1.loginServlet

package com.itheima.web;import com.itheima.mapper.UserMapper;import com.itheima.pojo.User;import com.itheima.util.SqlSessionFactoryUtils;import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder;import javax.servlet.*;import javax.servlet.Http.*;import javax.servlet.annotation.*;import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;@WebServlet("/loginServlet")public class loginServlet extends httpservlet {    @Override    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {        // 1.接收用户名和密码        String username = request.getParameter("username");        String password = request.getParameter("password");        //2. 调用Mybatis完成查询        SqlSessionFactory sqlSessionFactory = SqlSessionFactoryUtils.getSqlSessionFactory();        //2.2获取SqlSession对象        SqlSession sqlSession =sqlSessionFactory.openSession();        //2.3获取Mapper        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);        //2.4 调用方法        User user = userMapper.select(username, password);        //2.5释放资源        sqlSession.close();        // 获取相对应的输出流 并设置content        response.setContentType("text/html;charset=utf-8");        PrintWriter writer = response.getWriter();        //3.判断user是否为null        if (user!=null){            //登陆成功            writer.write("登陆成功");        }        else {            //登陆失败            writer.write("登陆失败");        }    }    @Override    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {        this.doGet(request, response);    }}

2.reGISterServlet

package com.itheima.web;import com.itheima.mapper.UserMapper;import com.itheima.pojo.User;import com.itheima.util.SqlSessionFactoryUtils;import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder;import javax.servlet.*;import javax.servlet.http.*;import javax.servlet.annotation.*;import java.io.IOException;import java.io.InputStream;@WebServlet("/registerServlet")public class registerServlet extends HttpServlet {    @Override    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {        //1.接受用户数据        String username = request.getParameter("username");        String password = request.getParameter("password");        // 封装用户对象        User user = new User();        user.setUsername(username);        user.setPassword(password);        // 调用Mapper，根据用户名来查询是否        SqlSessionFactory sqlSessionFactory = SqlSessionFactoryUtils.getSqlSessionFactory();        //2.2获取SqlSession对象        SqlSession sqlSession =sqlSessionFactory.openSession();        //2.3获取Mapper        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);        //2.4 调用方法        User u = userMapper.selectByUsername(username);        if (u == null){            // 用户名不存在            userMapper.add(user);            // 提交事务            sqlSession.commit();            response.setContentType("text/html;charset=utf-8");            response.getWriter().write("注册成功");        }        else{            // 用户名不存在            response.setContentType("text/html;charset=utf-8");            response.getWriter().write("用户已存在,注册失败");        }        // 释放资源        sqlSession.close();    }    @Override    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {        this.doGet(request, response);    }}

5.html

1.login.html

            
来源地址：https://blog.csdn.net/m0_64238843/article/details/129600091