SSM框架练习一(登录后关联数据表的业务模型）

需要实现的整体功能：

登录
反馈信息列表展示
查询反馈信息
发表反馈

1.数据库设计

创建数据库

创建表结构及其约束

添加测试数据

工具：PHP、Navicat

create table tab_user(
 id int primary key auto_increment,
 uname varchar(30) not null,
 pwd varchar(255) not null
);

insert into tab_user(uname,pwd)values('张散','123456');
insert into tab_user(uname,pwd)values('李思','123456');
insert into tab_user(uname,pwd)values('王武','123456');


select * from tab_user;


create table tab_feedback(
id int primary key auto_increment,
commit_time datetime,
title varchar(100) not null,
content varchar(255) not null,
open int,
author int references tab_user(id)
);

insert into tab_feedback(author,commit_time,title,content,open)values(1,'2021-05-24 15:21:48','反馈测试','我是反馈测试的内容',0);
insert into tab_feedback(author,commit_time,title,content,open)values(1,'2021-05-24 15:04:30','饭菜不好','食堂饭菜不好吃，建议引入高级厨师',1);
insert into tab_feedback(author,commit_time,title,content,open)values(2,'2021-05-24 15:02:43','噪音污染','学校旁工地晚上施工，影响休息',1);
insert into tab_feedback(author,commit_time,title,content,open)values(3,'2021-05-24 15:04:09','学校超市东西价格昂贵','学校超市一家独大，商品价格设置不合理',0);

select * from  tab_feedback;
delete from tab_feedback where id=3;
update tab_feedback set commit_time='2023-05-5 20:02:43',title='标题',content='内容',open='' where id =1;
select * from tab_feedback inner join tab_user on tab_feedback.author=tab_user.id

2.框架搭建

根据所用技术搭建项目框架；创建web项目导入jar包和js文件并部署到TomCat中

ssm框架配置;工具：IDEA

1.springmvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/mvc
       http://www.springframework.org/schema/mvc/spring-mvc.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd">
    <!--1.让springMVC框架只管理com.chen.controller-->
    <context:component-scan base-package="com.zhan.controller"/>
    <!--2.配置视图解析器-->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/"/>
        <property name="suffix" value=".jsp"/>
    </bean>
    <!--3.静态资源不拦截-->
    <mvc:resources mapping="/css/**" location="/css/"/>
    <mvc:resources mapping="/js/**" location="/js/"/>
    <mvc:resources mapping="/fonts/**" location="/fonts/"/>
    <mvc:resources mapping="/img/**" location="/img/"/>
    <!--4.开启注解驱动：默认会加载试图映射器和视图适配器-->
    <mvc:annotation-driven/>
</beans>

2.spring.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop.xsd">
    <!--1.让spring框架管理com.chen包中所有的对象，但是排除使用了Controller注解的类-->
    <context:component-scan base-package="com.zhan">
        <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>
    <!--2.让spring框架的jdbc管理数据库的连接-->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/test"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>
    <!--3.配置SqlSessionFactoryBean，把SqlSessionFactory对象交给IOC管理，他会自动创建
    sqlSession对象，会根据mapper接口再创建代理对象-->
    <bean id="factoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="typeAliasesPackage" value="com.zhan.bean"/>
        <property name="configLocation" value="classpath:mybatis.xml"/>
    </bean>
    <!--4.配置扫描器，扫描mapper文件，让mybatis知道要创建什么接口的实现类-->
    <bean id="scannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.zhan.dao"/>
    </bean>
</beans>

3.mybatis.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!--    <settings>-->
<!--        <setting name="logImpl" value="log4j"/>-->
<!--    </settings>-->
</configuration>

4.web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <!--1.配置监听器，检测servlet容器创建的时候加载 spring.xml-->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:spring.xml</param-value>
    </context-param>
    <!--2.配置核心控制器DispatcherServlet，创建的时候加载 springmvc.xml-->
    <servlet>
        <servlet-name>dispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:springmvc.xml</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    <!--3.配置字符集过滤器，设置中文编码-->
    <filter>
        <filter-name>encodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>utf-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>

配置完成后测试是否能够运行成功，页面是否跳转；

注意：按照规范:字段名、实体类属性、变量首字母要小写，类名要大写；

bean层：实体类User和Feedback

1.登录的业务逻辑

1.首先在前端设计一个表单，提交表单时根据name属性在后端的控制器中自动参数绑定:
2.后端根据获取到的用户名和密码执行数据库查询，判断用户是否可以登录:
3.登录后一定要把当前用户信息存入session中;

dao层：接口UserDao

@Repository
public interface UserDao {
    @Select("select * from tab_user where uname=#{uname}")
    User selectByName(String uname);
}

service层：接口UserService

public interface UserService {
    User selectByName(String uname);
}

实现类UserServiceImpl

@Service
public class UserServiceImpl implements UserService {
    @Autowired
    UserDao userDao;

    @Override
    public User selectByName(String uname) {
        return userDao.selectByName(uname);
    }
}

Controller层：UserController

@Controller
public class UserController {
    @Autowired
    UserService userService;

    @RequestMapping("/login")
    public ModelAndView login(String uname, String pwd, HttpSession session){
        ModelAndView mv = new ModelAndView();
//        System.out.println(uname);
//        System.out.println(pwd);
        User user = userService.selectByName(uname);
//        System.out.println(user);
        if(user!=null){
            if(user.getPwd().equals(pwd)){
                session.setAttribute("user",user);
                mv.setViewName("redirect:/findAll");
            }else {
                mv.addObject("error","密码错误！");
                mv.setViewName("error");
            }
        }else{
            mv.addObject("error","用户名不存在！");
            mv.setViewName("error");
        }
        return mv;
    }
}

登录页：login.jsp

οnsubmit=return check() 是一个HTML表单中的属性，表示在提交表单时调用一个名为check()的JavaScript函数来验证表单的输入是否合法。如果check()函数返回true，则表单提交成功，否则表单提交失败。

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>登录页</title>
    <script src="js/jquery.min.js"></script>
    <script>
        function check(){
            var uname = $("#uname").val();
            var pwd = $("#pwd").val();
            if(uname==null || uname==''){
                alert("用户名不能为空！")
                return false;
            }
            if(pwd==null || uname==''){
                alert("密码不能为空！")
                return false;
            }
            return true;
        }
    </script>
</head>
<body>
<h2>欢迎登录！</h2>
<form action="login" method="post" onsubmit="return check()">
    用户名：<input type="text" id="uname" name="uname" value=""/><br>
    密码：<input type="password" id="pwd" name="pwd" value=""/><br>
    <input type="submit" id="btn" value="登录"/>
</form>
</body>
</html>

错误页：error.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>错误页</title>
</head>
<body>
${error}
</body>
</html>

2.数据列表查询的业务逻辑

1.获取当前session中的用户对象;
2.根据用户的id执行数据表的关联查询:(mybatis中需要配置一对一的自动关联映射关系)
3.把查询的数据列表发送给主页，做数据展示;

dao层：接口FeedBackDao

@Repository
public interface FeedBackDao {
    List<Feedback> selectByAuthor(int author);
}

mapper映射：FeedBackDao.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.zhan.dao.FeedBackDao">
<!--定义自定义映射关系-->
    <resultMap id="fbMap" type="com.zhan.bean.Feedback">
        <id property="id" column="id"/>
        <result property="commit_time" column="commit_time"/>
        <result property="title" column="title"/>
        <result property="content" column="content"/>
        <result property="open" column="open"/>
<!--配置一对一映射：自动关联查询 使用外键author 执行该用户信息的查询，把查到的用户对象赋值给 实体类属性user-->
        <association property="user" column="author" select="com.zhan.dao.UserDao.selectById"></association>
    </resultMap>

    <select id="selectByAuthor" parameterType="int" resultMap="fbMap">
        select * from tab_feedback where author=#{author};
    </select>

</mapper>

service层：接口FeedBackService

public interface FeedBackService {
    List<Feedback> selectByAuthor(int author);
}

实现类FeedBackServiceImpl

@Service
public class FeedBackServiceImpl implements FeedBackService {
    @Autowired
    FeedBackDao feedBackDao;

    @Override
    public List<Feedback> selectByAuthor(int author) {
        return feedBackDao.selectByAuthor(author);
    }
}

Controller层：FeedBackController

@Controller
public class FeedBackController {
    @Autowired
    FeedBackService feedBackService;

    @RequestMapping("/findAll")
    public ModelAndView findAll(HttpSession session){
        ModelAndView mv = new ModelAndView();
        //查询当前登录用户发布的问题反馈
        User user = (User) session.getAttribute("user");
        System.out.println(user);
        //根据用户的id 查询 问题反馈表
        List<Feedback> feedbackList = feedBackService.selectByAuthor(user.getId());
        System.out.println(feedbackList);
        mv.addObject("feedbackList",feedbackList);
        mv.setViewName("zhuye");
        return mv;
    }
}

主页：zhuye.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!--fmt标签可以对日期进行转换和解析-->
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
<html>
<head>
    <title>主页</title>
</head>
<body>
<table>
    <thead>
    <tr>
        <th>编号</th>
        <th>反馈人</th>
        <th>反馈时间</th>
        <th>反馈标题</th>
        <th>反馈内容</th>
        <th>公开状态</th>
        <th>操作</th>
    </tr>
    </thead>
    <tbody>
    <c:forEach items="${feedbackList}" var="feedback">
        <td>${feedback.id}</td>
        <td>${feedback.user.uname}</td>
        <td><fmt:formatDate value="${feedback.commit_time}" pattern="yyyy-MM-dd HH:mm:ss"></fmt:formatDate></td>
        <td>${feedback.title}</td>
        <td>${feedback.content}</td>
        <td>
          <c:if test="${feedback.open==0}">不公开</c:if>
          <c:if test="${feedback.open==1}">公开</c:if>
        </td>
        <td>待定</td>
        </tr>
    </c:forEach>
    <tr>
    </tbody>
</table>
</body>
</html>

3.模糊查询

dao层：接口FeedBackDao

@Repository
public interface FeedBackDao {
    List<Feedback> seach(Feedback feedback);
}

mapper映射：FeedBackDao.xml

<select id="seach" parameterType="com.zhan.bean.Feedback" resultMap="fbMap">
        select * from tab_feedback where author=#{user.id} and title like concat('%',#{title},'%') and open=#{open};
</select>

service层：接口FeedBackService

public interface FeedBackService {
    List<Feedback> seach(Feedback feedback);
}

实现类FeedBackServiceImpl

@Service
public class FeedBackServiceImpl implements FeedBackService {
    @Autowired
    FeedBackDao feedBackDao;

    @Override
    public List<Feedback> seach(Feedback feedback) {
        return feedBackDao.seach(feedback);
    }
}

Controller层：FeedBackController

@RequestMapping("/seach")
    public ModelAndView seach(Feedback feedback,HttpSession session){
        ModelAndView mv = new ModelAndView();
        feedback.setUser((User) session.getAttribute("user"));
        List<Feedback> feedbackList = feedBackService.seach(feedback);
        mv.addObject("feedbackList",feedbackList);
        mv.setViewName("zhuye");
        return mv;
    }

zhuye.jsp补充

<form action="seach" method="post">
    公开状态<select name="open">
    <option value="1">公开</option>
    <option value="0">不公开</option>
</select>
    反馈标题：<input type="text" id="title" name="title" value="">
    <input type="submit" id="btn" value="查询">
</form>

4.信息的添加的业务逻辑

1.设计表单，录入数据信息，提交表单时根据name属性在后端的控制器中使用实体类自动参数绑定
2.添加时，页面录入数据和数据库字段数量不一致，此时需要后端进行数据的补充确保数据库字段所有的数据准备够;
---用户信息的补充后端是通过session获得当前登录的用户;
---时间默认是当前时间;
---某些状态在后端赋默认状态值;
--某些字段是通过计算得到的;
3.补充数据库添加所需要的全部数据库，执行数据库插入操作;

dao层：接口FeedBackDao

@Repository
public interface FeedBackDao {
    int insert(Feedback feedback);
}

mapper映射：FeedBackDao.xml补充

    <insert id="insert" parameterType="com.zhan.bean.Feedback">
        insert into tab_feedback(commit_time,title,content,open,author)
        values(#{commit_time},#{title},#{content},#{open},#{user.id});
    </insert>

service层：接口FeedBackService

public interface FeedBackService {
    int insert(Feedback feedback);
}

实现类FeedBackServiceImpl

@Service
public class FeedBackServiceImpl implements FeedBackService {
    @Autowired
    FeedBackDao feedBackDao;

    @Override
    public int insert(Feedback feedback) {
        return feedBackDao.insert(feedback);
    }
}

Controller层：FeedBackController补充

    @RequestMapping("/add")
    public ModelAndView add(Feedback feedback,HttpSession session){
        ModelAndView mv = new ModelAndView();
        System.out.println("前端提交的数据："+feedback);
        User user = (User) session.getAttribute("user");
        feedback.setUser(user);
        System.out.println("前端提交的数据："+feedback);
        int n = feedBackService.insert(feedback);
        if(n>0){
            mv.setViewName("redirect:/findAll");
        }else{
            mv.addObject("error","添加商品出错啦！");
            mv.setViewName("error");
        }
        return mv;
    }

zhuye.jsp补充

<h3>
    <a href="add.jsp">发表反馈</a>
</h3>

5.删除的业务逻辑

1.在主页设计一个超链接，指定请求的地址并通过?传递给后端主键id;
2.在后端控制器获得id，并进行数据的删除操作;
3.判断受影响的行数大于0，则重新请求findAll，再次查询最新的数据并跳转到主页:
5.修改
业务逻辑:
1.在主页设计一个超链接，指定请求的地址并通过?传递给后端主键id:
2.后端根据id查询完整信息，然后把数据显示在数据展示页面的表单元素中:
3.用户根据需要修改字段的值，点击修改把最新数据提交给后端:
修改的时候也可能是变化的，记住一点，前端提供的值不够，后端需要补充!!!!!
-用户信息的补充后端是通过session获得当前登录的用户:
--时间默认是当前时间;
-某些状态在后端赋默认状态值;
-某些字段是通过计算得到的: I
4.后端拿到最新的数据进行数据库的更新操作;

dao层：接口FeedBackDao

@Repository
public interface FeedBackDao {
    int delete(int id);
}

mapper映射：FeedBackDao.xml补充

    <delete id="delete" parameterType="int">
        delete from tab_feedback where id = #{id};
    </delete>

service层：接口FeedBackService补充

public interface FeedBackService {
     int delete(int id);
}

实现类FeedBackServiceImpl

@Service
public class FeedBackServiceImpl implements FeedBackService {
    @Autowired
    FeedBackDao feedBackDao;

    @Override
    public int delete(int id) {
        return feedBackDao.delete(id);
    }
}

Controller层：FeedBackController

@RequestMapping("/del")
    public ModelAndView del(int id){
        ModelAndView mv=new ModelAndView();
        int i = feedBackService.delete(id);
        if(i>0){
            mv.setViewName("redirect:/findAll");
        }else{
            mv.addObject("error","删除商品出错啦！");
            mv.setViewName("error");
        }
        return mv;
    }

zhuye.jsp补充

        <td>
            <%--待定--%>
            <a href="del?id=${feedback.id}">删除</a>
        </td>

6.修改的业务逻辑

1.在主页设计一个超链接，指定请求的地址并通过?传递给后端主键id;
2.后端根据id查询完整信息，然后把数据显示在数据展示页面的表单元素中:
3.用户根据需要修改字段的值，点击修改把最新数据提交给后端;
修改的时候也可能是变化的，记住一点，前端提供的值不够，后端需要补充!!!!!
-用户信息的补充后端是通过session获得当前登录的用户;
-时间默认是当前时间:
--某些状态在后端赋默认状态值;
--某些字段是通过计算得到的:
4.后端拿到最新的数据进行数据库的更新操作:对
5.判断受影响的行数大于0，则重新请求findAll，再次查询最新的数据井跳转到主页;

dao层：接口FeedBackDao

@Repository
public interface FeedBackDao {
    Feedback selectById(int id);
    int update(Feedback feedback);
}

mapper映射：FeedBackDao.xml补充

    <select id="selectById" parameterType="int" resultMap="fbMap">
        select * from tab_feedback where id=#{id};
    </select>
    <update id="update" parameterType="com.zhan.bean.Feedback">
        update tab_feedback set commit_time=#{commit_time},title=#{title},content=# 
        {content},open=#{open} where id=#{id};
    </update>

service层：接口FeedBackService

public interface FeedBackService {
     Feedback selectById(int id);
    int update(Feedback feedback);
}

实现类FeedBackServiceImpl

@Service
public class FeedBackServiceImpl implements FeedBackService {
    @Autowired
    FeedBackDao feedBackDao;

    @Override
    public Feedback selectById(int id) {
        return feedBackDao.selectById(id);
    }

    @Override
    public int update(Feedback feedback) {
        return feedBackDao.update(feedback);
    }
}

Controller层：FeedBackController

    @RequestMapping("/findById")
    public ModelAndView findById(int id){
        ModelAndView mv=new ModelAndView();
        Feedback feedback = feedBackService.selectById(id);
        mv.addObject("feedback",feedback);
        mv.setViewName("show");
        return mv;
    }

    @RequestMapping("/update")
    public ModelAndView update(Feedback feedback){
        ModelAndView mv=new ModelAndView();
        int i = feedBackService.update(feedback);
        if(i>0){
            mv.setViewName("redirect:/findAll");
        }else{
            mv.addObject("error","修改商品出错啦！");
            mv.setViewName("error");
        }
        return mv;
    }

zhuye.jsp补充

        <td>
            <%--待定--%>
            <a href="findById?id=${feedback.id}">修改</a>
        </td>

补充修改页：show.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
    <title>修改页</title>
</head>
<body>
  <h2>修改页</h2>
  <form action="update" method="post">
    <input type="hidden" id="id" name="id" readonly="readonly" value="${feedback.id}">
    反馈人：<input type="text" id="uname" name="user.uname" readonly="readonly" value="${feedback.user.uname}"> <br>
    反馈时间：<input type="date" id="commit_time" name="commit_time" value="<fmt:formatDate value="${feedback.commit_time}" pattern="yyyy-MM-dd"></fmt:formatDate>"> <br>
    反馈标题：<input type="text" id="title" name="title" value="${feedback.title}"> <br>
    反馈内容：<input type="text" id="content" name="content" value="${feedback.content}"> <br>

    是否公开：<input type="radio" name="open" <c:if test="${feedback.open==1}">checked="checked"</c:if> value="1">公开
             <input type="radio" name="open" <c:if test="${feedback.open==0}">checked="checked"</c:if> value="0">不公开 <br>
    <input type="submit" id="btn" value="修改"> <br>
  </form>
</body>
</html>

页面效果

补充知识

EL表达式获取对象的属性通过的是getter方法

字段转义

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

<c:if test="${feedback.open==1}">checked="checked"</c:if>

    //springmvc框架默认支持的格式是：yyyy/MM/dd 也可以通过注解
    @DateTimeFormat(pattern = "yyyy-MM-dd")
    //@DateTimeFormat(pattern = "yyyy-MM-dd'T'HH:mm")
    private Date commit_time;

日期转义

<!--fmt标签可以对日期进行转换和解析-->
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>

反馈时间：<input type="date" id="commit_time" name="commit_time" value="<fmt:formatDate value="${feedback.commit_time}" pattern="yyyy-MM-dd"></fmt:formatDate>"> <br>

<fmt:formatDate value="${feedback.commit_time}" pattern="yyyy-MM-dd HH:mm:ss"></fmt:formatDate>