一《学生教务系统》之城市管理板块实现

Posted 2021-12-05 程序员小王java

《学生教务系统》之城市管理板块实现

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一、城市管理实现前提

注意：在实现城市功能之前我们可以参考一下：《学生教务系统》立项需求说明书

（1）城市管理实现思路图

2、城市管理数据库设计(t_city)

字段	类型	主键	约束	备注
c_id	int	是	自增	编号
c_name	varchar(20)		not null unique	名称

注意：其中Studnet表中有t_city，所以我们建表时最好把城市表放在第一个建的表

create table t_city(
  id int primary key auto_increment ,
  name varchar(20) not null  unique
)

3、城市管理页面实现效果图

二、查询，删除，添加功能实现

（1）实体类（bean类）

public class City implements Serializable {
    private Integer cid;
    private String cname;

（2）dao接口

public interface CityDao{
    /**
     * 添加城市
     * @param city
     */
    public void insertCity(City city);

    /**
     * 删除城市
     * @param id
     */
    public void deleteCity(Integer id);

    /**
     * 查询所有
     * @return
     */
    public List<City> selectCity();
}

（3）Mybatis实现Dao接口

<mapper namespace="com.tjcu.dao.CityDao">

    <!--动态SQL语句-->
    <resultMap id="SelectCity" type="city">
        <id property="cid" column="c_id"></id>
        <result property="cname" column="c_name"></result>
    </resultMap>
    
    <!--添加城市-->
    <insert id="insertCity">
        insert into t_city
        values (#{cid}, #{cname})
    </insert>
    
    <!--删除城市-->
    <delete id="deleteCity">
        delete
        from t_city
        where c_id = #{id}
    </delete>
    
    <!--查询所有-->
    <select id="selectCity" resultMap="SelectCity">
        select c_id, c_name
        from t_city
    </select>

</mapper>

（4）Service接口和Service的实现类

• Service接口

public interface CityService {
    /**
     * 添加城市
     * @param city
     */
    public void insertCity(City city);

    /**
     * 删除城市
     * @param id
     */
    public void deleteCity(Integer id);

    /**
     * 查询所有
     * @return
     */
    public List<City> selectCity();
}

• Service实现

public class CityServiceImpl implements CityService {
    @Override
    public void insertCity(City city) {
        CityDao mapper = (CityDao) MybatisUtil.getMapper(CityDao.class);
        mapper.insertCity(city);
        MybatisUtil.commit();
    }

    @Override
    public void deleteCity(Integer id) {
        CityDao mapper = (CityDao) MybatisUtil.getMapper(CityDao.class);
        mapper.deleteCity(id);
        MybatisUtil.commit();
    }

    @Override
    public List<City> selectCity() {
        CityDao mapper = (CityDao) MybatisUtil.getMapper(CityDao.class);
        List<City> cities = mapper.selectCity();
        MybatisUtil.close();
        return cities;
    }

（5）Struts2实现Controller层

public class CityAction extends ActionSupport {
    private City city;
    private  List<City> cities;
    //添加城市
    public String insertCity() {
        CityService cityService = new CityServiceImpl();
        city.setCid(null);
        cityService.insertCity(city);
       return  SUCCESS;
    }
    //删除城市
    public String deleteCity() {
        CityService cityService = new CityServiceImpl();
        cityService.deleteCity(city.getCid());
        return  SUCCESS;
    }
   //展示成
    public String selectCity() {
        CityService cityService = new CityServiceImpl();
         cities = cityService.selectCity();
        return SUCCESS;
    }

    public City getCity() {
        return city;
    }

    public void setCity(City city) {
        this.city = city;
    }

    public List<City> getCities() {
        return cities;
    }

    public void setCities(List<City> cities) {
        this.cities = cities;
    }

（6）测试类

public class CityTest {
    @Test
    public void insert(){
        CityService cityService = new CityServiceImpl();
        City city = new City(null, "天津");
        cityService.insertCity(city);

    }
    @Test
    public void delete(){
        CityService cityService = new CityServiceImpl();
        cityService.deleteCity(2);
    }
    @Test
    public void select(){
        CityService cityService = new CityServiceImpl();
        List<City> cities = cityService.selectCity();
        for (City city : cities) {
            System.out.println(city);
        }
    }

（7）Web.xml中struts2过滤器配置（过滤器只需要配置，后续模块功能不再配置）

  <filter>
    <filter-name>struts</filter-name>
    <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
  </filter>
  
  <filter-mapping>
    <filter-name>struts</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

（8）Struts核心配置

<!--城市-->
    <package name="city" namespace="/city" extends="struts-default">
        <!--添加城市-->
        <action name="addCity" method="insertCity" class="com.tjcu.action.CityAction">
            <result name="success" type="redirectAction">showCity</result>
        </action>
        <!--删除城市-->
        <action name="dropCity" method="deleteCity" class="com.tjcu.action.CityAction">
            <result name="success" type="redirectAction">showCity</result>
        </action>
        <!--展示城市-->
        <action name="showCity" method="selectCity" class="com.tjcu.action.CityAction">
            <result name="success" type="dispatcher">/city/showCity.jsp</result>
        </action>
    </package>

（9）JSP页面

• 展示（删除）城市页面

<%@ page language="java" contentType="text/html; charset=utf-8"
         pageEncoding="utf-8" isELIgnored="false" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
<html lang="en">
<head>
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <link rel="stylesheet" type="text/css" href="${pageContext.request.contextPath}/statics/css/bootstrap.min.css">
    <title>城市列表</title>
</head>
<body>

<div class="container-fluid">
    <div class="row">
        <div class="col-sm-12">
            <input type="button" class="btn btn-success btn-sm" value="添加城市" onclick="location.href='addCity.jsp'"/>
        </div>
    </div>
    <div class="row" style="margin-top: 15px;">
        <div class="col-sm-12">
            <table class="table table-striped table-bordered table-hover">
                <tr>
                    <th>编号</th>
                    <th>名称</th>
                    <th>操作</th>
                </tr>
                <c:forEach var="city" items="${requestScope.cities}" varStatus="c">
                    <tr>
                        <%--使用jstl+EL进行排序--%>
                        <td>${c.count}</td>
                        <td>${city.cname}</td>
                        <td>
                            <a href="${pageContext.request.contextPath}/city/dropCity?city.cid=${city.cid}" class="btn btn-danger btn-sm">删除</a>
                        </td>
                    </tr>
                </c:forEach>
            </table>
        </div>

    </div>

</div>


</body>
</html>

• 添加城市页面

<%@ page language="java" contentType="text/html; charset=utf-8"
         pageEncoding="utf-8" isELIgnored="false" %>
<html lang="en">
<head>
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <link rel="stylesheet" type="text/css" href="../statics/css/bootstrap.min.css">
    <title>添加城市</title>
</head>
<body>
<div class="container-fluid">
    <div class="row">
        <div class="col-sm-12">
            <form action="${pageContext.request.contextPath}/city/addCity" method="post">
                <div class="form-group">
                    <label>
                        城市名称:
                    </label>
                    <input type="text" class="form-control" name="city.cname"/>
                </div>

                <input type="submit" class="btn btn-success btn-block btn-sm" value="提交"/>
                <input type="button" class="btn btn-info btn-block btn-sm" value="返回上级" onclick="history.go(-1);"/>
            </form>
        </div>
    </div>
</div>

</body>
</html>

下一个功能是： 标签功能模块的实现代码

📌 作者：王恒杰

📃 更新： 2021.11.3

❌ 勘误： 无

📜 声明： 由于作者水平有限，本文有错误和不准确之处在所难免，本人也很想知道这些错误，恳望读者批评指正！
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