• springboot:视图渲染技术

    目录

    一、Freemarker入门

    application.yml

    配置可使用的Freemarker界面

    index.ftl

     IndexController 

    二、Freemarker的基本语法

    整合

    IndexController 

    index.ftl

    注意

    common.ftl

    application.yml

    三、Freemarker综合案例

    准备好现项目所需ssm中的代码

    Clazz 

    application.yml

    ClazzMapper 

    ClazzMapper.xml

    ClazzBiz 

    PageBean 

     StringUtils 

     ClazzBizImpl 

    整合aop pageHelper插件

     PagerAspect 

     application.yml

    jsp->freemaker

    clzList.ftl

    clzEdit.ftl

    ClazzController 

    Springboot04Application 

     application.yml

     实现分页功能

    FreemarkerPageHelper 

     ClazzController 

    一、Freemarker入门

    官方学习网址：什么是 FreeMarker? - FreeMarker 中文官方参考手册

    新建一个模块 勾选以下的组件

     pom.xml中数据库的版本降低

     调整

    application.yml

    1. mybatis:
    2.     mapper-locations: classpath:mappers/*xml
    3.     type-aliases-package: com.cdl.springboot04.mybatis.entity
    4. server:
    5.     port: 8080
    6. spring:
    7.     application:
    8.         name: springboot04
    9.     datasource:
    10.         driver-class-name: com.mysql.jdbc.Driver
    11.         name: defaultDataSource
    12.         password: 123456
    13.         url: jdbc:mysql://localhost:3306/mysql?useUnicode=true&characterEncoding=UTF-8&useSSL=false
    14.         username: root
    15.     freemarker:
    16.         cache: false
    17.         charset: utf-8
    18.         expose-request-attributes: true
    19.         expose-session-attributes: true
    20.         suffix: .ftl
    21.         template-loader-path: classpath:/templates/
    22. #    resources:
    23. #       static-locations: classpath:/static/# 应用服务 WEB 访问端口
    24.     mvc:
    25.         static-path-pattern: classpath:/static/

    测试：

    配置可使用的Freemarker界面

     

     

     

     

     新建一个Freemarker的界面

    index.ftl

    1. HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    2.         "http://www.w3.org/TR/html4/loose.dtd">
    3. <html>
    4. <head>
    5.     <title>title>
    6. head>
    7. <body>
    8. 欢迎来到 Freemaker 首页
    9. body>
    10. html>

     IndexController 

    1. package com.cdl.springboot04.controller;
    2.  
    3. import org.springframework.stereotype.Controller;
    4. import org.springframework.web.bind.annotation.RequestMapping;
    5.  
    6. /**
    7.  * @author cdl
    8.  * @site www.cdl.com
    9.  * @create 2022-11-01 18:33
    10.  */
    11. @Controller
    12. public class IndexController {
    13.  
    14.     @RequestMapping("/")
    15.     public String index(){
    16.         System.out.println("come in ...");
    17. //         suffix: .ftl
    18. //        template-loader-path: classpath:/templates/
    19. //        /templates/index.ftl
    20.         return "index";
    21.     }
    22.  
    23. }

    在启动类运行

     访问成功

    二、Freemarker的基本语法

    提供默认值

    后台代码

    1. package com.cdl.springboot04.controller;
    2.  
    3. import org.springframework.stereotype.Controller;
    4. import org.springframework.ui.Model;
    5. import org.springframework.web.bind.annotation.GetMapping;
    6. import org.springframework.web.bind.annotation.RequestMapping;
    7. import org.springframework.web.servlet.ModelAndView;
    8.  
    9. import java.util.ArrayList;
    10.  
    11. /**
    12.  * @author cdl
    13.  * @site www.cdl.com
    14.  * @create 2022-11-01 18:33
    15.  */
    16. @Controller
    17. public class IndexController {
    18.  
    19. //    @RequestMapping("/")
    20. //    public ModelAndView index(){
    21.         //第一种写法
    22. //        ModelAndView mv = new ModelAndView();
    23. //        mv.setViewName("index");
    24. //        mv.addObject("uname","小陈");
    25. //        System.out.println("come in ...");
    26.          suffix: .ftl
    27.         template-loader-path: classpath:/templates/
    28.         /templates/index.ftl
    29. //        return mv;
    30.  
    31. //    }
    32.  
    33.     @GetMapping("/")
    34.     public String index(Model model) {
    35.         System.out.println("come in............");
    36.         model.addAttribute("uname", "小刘");
    37.         model.addAttribute("sex", "girl");
    38.         return "index";
    39.     }
    40.  
    41.  
    42. }

    前端代码

    1. HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    2.         "http://www.w3.org/TR/html4/loose.dtd">
    3. <html>
    4. <head>
    5.     <title>title>
    6. head>
    7. <body>
    8. <#--欢迎来到 Freemaker 首页-->
    9. <h3>取值h3>
    10. <p>提供默认值p>
    11. <#--当接受的参数值不为空，这个问题是需要避免的-->
    12. <#--${uname}-->
    13. ${uname !}
    14. body>
    15. html>

    前端结果

    当后台没有传值的时候 

    ${uname ! "小王"} 结果是小王的默认值

    整合

    后台

    IndexController 

    1. package com.cdl.springboot04.controller;
    2.  
    3. import com.cdl.springboot04.entity.User;
    4. import org.springframework.stereotype.Controller;
    5. import org.springframework.ui.Model;
    6. import org.springframework.web.bind.annotation.GetMapping;
    7.  
    8. import java.util.ArrayList;
    9. import java.util.List;
    10.  
    11. /**
    12.  * @author cdl
    13.  * @site www.cdl.com
    14.  * @create 2022-11-01 18:33
    15.  */
    16. @Controller
    17. public class IndexController {
    18.  
    19. //    @RequestMapping("/")
    20. //    public ModelAndView index(){
    21.         //第一种写法
    22. //        ModelAndView mv = new ModelAndView();
    23. //        mv.setViewName("index");
    24. //        mv.addObject("uname","小陈");
    25. //        System.out.println("come in ...");
    26.          suffix: .ftl
    27.         template-loader-path: classpath:/templates/
    28.         /templates/index.ftl
    29. //        return mv;
    30.  
    31. //    }
    32.  
    33.     @GetMapping("/")
    34.     public String index(Model model) {
    35.         System.out.println("come in............");
    36.         model.addAttribute("uname", "小刘");
    37.         model.addAttribute("sex", "girl");
    38.         List lst = new ArrayList<>();
    39.         lst.add(new User(1, "zs"));
    40.         lst.add(new User(2, "ls"));
    41.         lst.add(new User(3, "ww"));
    42.  
    43.         model.addAttribute("lst",lst);
    44.         model.addAttribute("arr", new Integer[]{5, 6, 7, 8, 9});
    45.         return "index";
    46.     }
    47.  
    48.  
    49.  
    50. }

    前端

    index.ftl

    1. HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    2.         "http://www.w3.org/TR/html4/loose.dtd">
    3. <html>
    4. <head>
    5.     <title>title>
    6. head>
    7. <body>
    8. <#--欢迎来到 Freemaker 首页-->
    9. <h3>取值h3>
    10. <p>提供默认值p>
    11. <#--当接受的参数值不为空，这个问题是需要避免的-->
    12. <#--${uname}-->
    13. ${uname ! "小王"}
    14.  
    15. <h3>对null值先进行判断h3>
    16. <p>exists用在逻辑判断p>
    17. <#if uname?exists>
    18.     ${uname}
    20. <br>
    21.  
    22. <p>??是判断对象是否为空p>
    23. <#if uname??>
    24.     ${uname}
    26. <br>
    27.  
    28. <p>if_exists用来打印东西p>
    29. ${uname?if_exists}
    30. <br>
    31.  
    32.  
    33. <h3>2.条件h3>
    34. <#if sex=='nv'>
    35.     女
    36. <#elseif sex='nan'>
    37.     男
    38. <#else>
    39.     未知
    41. <br>
    42.  
    43.  
    44. <h3>3.循环h3>
    45. <p>1）取出数组中的元素p>
    46. <#list arr as a>
    47.     ${a}==
    49. <br>
    50. <p>2）取出集合中的对象（注：访问的类要被public所修饰）p>
    51. <#list lst as item>
    52.     ${item.id} : ${item.name}    <br>
    54.  
    55. <h3>4 include指令h3>
    56. <#include "/common.ftl" >
    57.  
    58. <h3>5 局部变量(assign)/全局变量(global)h3>
    59. ${ctx} :${ctx2}
    60.  
    61. body>
    62. html>

    注意

    common.ftl

    1. <#assign ctx>
    2.     ${springMacroRequestContext.contextPath}
    4. <#global ctx2>
    5.     ${springMacroRequestContext.contextPath}
    7.

    application.yml

    1. mybatis:
    2.     mapper-locations: classpath:mappers/*xml
    3.     type-aliases-package: com.cdl.springboot04.mybatis.entity
    4. server:
    5.     port: 8080
    6.     servlet:
    7.         context-path: /springboot04
    8. spring:
    9.     application:
    10.         name: springboot04
    11.     datasource:
    12.         driver-class-name: com.mysql.jdbc.Driver
    13.         name: defaultDataSource
    14.         password: 123456
    15.         url: jdbc:mysql://localhost:3306/mysql?useUnicode=true&characterEncoding=UTF-8&useSSL=false
    16.         username: root
    17.     freemarker:
    18.         cache: false
    19.         charset: utf-8
    20.         expose-request-attributes: true
    21.         expose-session-attributes: true
    22.         suffix: .ftl
    23.         template-loader-path: classpath:/templates/
    24. #    resources:
    25. #       static-locations: classpath:/static/# 应用服务 WEB 访问端口
    26.     mvc:
    27.         static-path-pattern: classpath:/static/

    三、Freemarker综合案例

    利用Freemarker完成基本的增删改查，参照之前ssm项目进行改造

    准备好现项目所需ssm中的代码

    新建一个model 的包 将之前ssm项目中的Clazz类复制进来 

    Clazz 

    1. package com.cdl.springboot04.model;
    2.  
    3.  
    4. import com.sun.istack.internal.NotNull;
    5. import lombok.AllArgsConstructor;
    6. import lombok.Data;
    7. import lombok.NoArgsConstructor;
    8.  
    9. /**
    10.  * NotNull:针对的是基本数据类型
    11.  *  @NotEmpty 作用于集合
    12.  *  @NotBlank    作用于字符串
    13.  */
    14. @Data
    15. @NoArgsConstructor
    16. @AllArgsConstructor
    17. public class Clazz {
    18.     protected Integer cid;
    19.  
    20.     protected String cname;
    21.  
    22.     protected String cteacher;
    23.  
    24.     protected String pic;
    25.  
    26.  
    27. }

    注意：扫描包的更改

    application.yml

    1. mybatis:
    2.     mapper-locations: classpath:mappers/*xml
    3.     type-aliases-package: com.cdl.springboot04.model
    4. server:
    5.     port: 8080
    6.     servlet:
    7.         context-path: /springboot04
    8. spring:
    9.     application:
    10.         name: springboot04
    11.     datasource:
    12.         driver-class-name: com.mysql.jdbc.Driver
    13.         name: defaultDataSource
    14.         password: 123456
    15.         url: jdbc:mysql://localhost:3306/mysql?useUnicode=true&characterEncoding=UTF-8&useSSL=false
    16.         username: root
    17.     freemarker:
    18.         cache: false
    19.         charset: utf-8
    20.         expose-request-attributes: true
    21.         expose-session-attributes: true
    22.         suffix: .ftl
    23.         template-loader-path: classpath:/templates/
    24. #    resources:
    25. #       static-locations: classpath:/static/# 应用服务 WEB 访问端口
    26.     mvc:
    27.         static-path-pattern: classpath:/static/

    新建一个mapper的包 将对应的mapper复制进去

    ClazzMapper 

    1. package com.cdl.springboot04.mapper;
    2.  
    3. import com.cdl.springboot04.model.Clazz;
    4. import org.springframework.stereotype.Repository;
    5.  
    6. import java.util.List;
    7. import java.util.Map;
    8.  
    9. @Repository
    10. public interface ClazzMapper {
    11.     int deleteByPrimaryKey(Integer cid);
    12.  
    13.     int insert(Clazz record);
    14.  
    15.     int insertSelective(Clazz record);
    16.  
    17.     Clazz selectByPrimaryKey(Integer cid);
    18.  
    19.     List listPager(Clazz clazz);
    20.  
    21.     List listMapPager(Clazz clazz);
    22.  
    23.     int updateByPrimaryKeySelective(Clazz record);
    24.  
    25.     int updateByPrimaryKey(Clazz record);
    26. }

    将mapper.xml的文件放入resources下的mapper中

    ClazzMapper.xml

    1. "1.0" encoding="UTF-8" ?>
    2. mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
    3. <mapper namespace="com.cdl.springboot04.mapper.ClazzMapper" >
    4.   <resultMap id="BaseResultMap" type="com.cdl.springboot04.model.Clazz" >
    5.     <constructor >
    6.       <idArg column="cid" jdbcType="INTEGER" javaType="java.lang.Integer" />
    7.       <arg column="cname" jdbcType="VARCHAR" javaType="java.lang.String" />
    8.       <arg column="cteacher" jdbcType="VARCHAR" javaType="java.lang.String" />
    9.       <arg column="pic" jdbcType="VARCHAR" javaType="java.lang.String" />
    10.     constructor>
    11.   resultMap>
    12.   <sql id="Base_Column_List" >
    13.     cid, cname, cteacher, pic
    14.   sql>
    15.   <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
    16.     select 
    17.     <include refid="Base_Column_List" />
    18.     from t_struts_class
    19.     where cid = #{cid,jdbcType=INTEGER}
    20.   select>
    21.  
    22.   <select id="listMapPager" resultType="java.util.Map" parameterType="Clazz" >
    23.     select
    24.     <include refid="Base_Column_List" />
    25.     from t_struts_class
    26.     <where>
    27.       <if test="cname != null and cname != ''">
    28.          and cname like CONCAT('%',#{cname},'%')
    29.       if>
    30.       <if test="cid != null and cid != ''">
    31.         and cid = #{cid}
    32.       if>
    33.     where>
    34.   select>
    35.  
    36.   <select id="listPager" resultType="com.cdl.springboot04.model.Clazz" parameterType="Clazz" >
    37.     select
    38.     <include refid="Base_Column_List" />
    39.     from t_struts_class
    40.     <where>
    41.       <if test="cname != null and cname != ''">
    42.         and cname like CONCAT('%',#{cname},'%')
    43.       if>
    44.       <if test="cid != null and cid != ''">
    45.         and cid = #{cid}
    46.       if>
    47.     where>
    48.   select>
    49.  
    50.   <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
    51.     delete from t_struts_class
    52.     where cid = #{cid,jdbcType=INTEGER}
    53.   delete>
    54.   <insert id="insert" parameterType="Clazz" >
    55.     insert into t_struts_class (cid, cname, cteacher, 
    56.       pic)
    57.     values (#{cid,jdbcType=INTEGER}, #{cname,jdbcType=VARCHAR}, #{cteacher,jdbcType=VARCHAR}, 
    58.       #{pic,jdbcType=VARCHAR})
    59.   insert>
    60.   <insert id="insertSelective" parameterType="Clazz" >
    61.     insert into t_struts_class
    62.     <trim prefix="(" suffix=")" suffixOverrides="," >
    63.       <if test="cid != null" >
    64.         cid,
    65.       if>
    66.       <if test="cname != null" >
    67.         cname,
    68.       if>
    69.       <if test="cteacher != null" >
    70.         cteacher,
    71.       if>
    72.       <if test="pic != null" >
    73.         pic,
    74.       if>
    75.     trim>
    76.     <trim prefix="values (" suffix=")" suffixOverrides="," >
    77.       <if test="cid != null" >
    78.         #{cid,jdbcType=INTEGER},
    79.       if>
    80.       <if test="cname != null" >
    81.         #{cname,jdbcType=VARCHAR},
    82.       if>
    83.       <if test="cteacher != null" >
    84.         #{cteacher,jdbcType=VARCHAR},
    85.       if>
    86.       <if test="pic != null" >
    87.         #{pic,jdbcType=VARCHAR},
    88.       if>
    89.     trim>
    90.   insert>
    91.   <update id="updateByPrimaryKeySelective" parameterType="Clazz" >
    92.     update t_struts_class
    93.     <set >
    94.       <if test="cname != null" >
    95.         cname = #{cname,jdbcType=VARCHAR},
    96.       if>
    97.       <if test="cteacher != null" >
    98.         cteacher = #{cteacher,jdbcType=VARCHAR},
    99.       if>
    100.       <if test="pic != null" >
    101.         pic = #{pic,jdbcType=VARCHAR},
    102.       if>
    103.     set>
    104.     where cid = #{cid,jdbcType=INTEGER}
    105.   update>
    106.   <update id="updateByPrimaryKey" parameterType="Clazz" >
    107.     update t_struts_class
    108.     set cname = #{cname,jdbcType=VARCHAR},
    109.       cteacher = #{cteacher,jdbcType=VARCHAR},
    110.       pic = #{pic,jdbcType=VARCHAR}
    111.     where cid = #{cid,jdbcType=INTEGER}
    112.   update>
    113. mapper>

    新建一个biz的包 放接口

    ClazzBiz 

    1. package com.cdl.springboot04.biz;
    2.  
    3. import com.cdl.springboot04.model.Clazz;
    4. import com.cdl.springboot04.util.PageBean;
    5. import org.springframework.cache.annotation.CacheEvict;
    6. import org.springframework.cache.annotation.CachePut;
    7.  
    8. import java.util.List;
    9. import java.util.Map;
    10.  
    11. public interface ClazzBiz {
    12.     int deleteByPrimaryKey(Integer cid);
    13.  
    14.     int insert(Clazz record);
    15.  
    16.     int insertSelective(Clazz record);
    17.  
    18.     Clazz selectByPrimaryKey(Integer cid);
    19.  
    20.     int updateByPrimaryKeySelective(Clazz record);
    21.  
    22.     int updateByPrimaryKey(Clazz record);
    23.  
    24.     List listPager(Clazz clazz, PageBean pageBean);
    25.     List listMapPager(Clazz clazz, PageBean pageBean);
    26. }

     将对应的工具类拿过来

    PageBean 

    1. package com.cdl.springboot04.util;
    2.  
    3. import java.util.HashMap;
    4. import java.util.Map;
    5.  
    6. import javax.servlet.http.HttpServletRequest;
    7.  
    8. /**
    9.  * 分页工具类
    10.  *
    11.  */
    12. public class PageBean {
    13.  
    14. 	private int page = 1;// 页码
    15.  
    16. 	private int rows = 10;// 页大小
    17.  
    18. 	private int total = 0;// 总记录数
    19.  
    20. 	private boolean pagination = true;// 是否分页
    21. 	
    22. 	private String url; //保存上一次请求的URL
    23. 	
    24. 	private Map paramMap = new HashMap<>();// 保存上一次请求的参数
    25. 	
    26. 	/**
    27. 	 * 初始化pagebean的，保存上一次请求的重要参数
    28. 	 * @param req
    29. 	 */
    30. 	public void setRequest(HttpServletRequest req) {
    31. //		1.1	需要保存上一次请求的URL
    32. 		this.setUrl(req.getRequestURL().toString());
    33. //		1.2	需要保存上一次请求的参数	bname、price
    34. 		this.setParamMap(req.getParameterMap());
    35. //		1.3	需要保存上一次请求的分页设置	pagination
    36. 		this.setPagination(req.getParameter("pagination"));
    37. //		1.4	需要保存上一次请求的展示条目数
    38. 		this.setRows(req.getParameter("rows"));
    39. //		1.5  初始化请求的页码	page
    40. 		this.setPage(req.getParameter("page"));
    41. 	}
    42. 	
    43. 	public void setPage(String page) {
    44. 		if(StringUtils.isNotBlank(page))
    45. 			this.setPage(Integer.valueOf(page));
    46. 	}
    47.  
    48. 	public void setRows(String rows) {
    49. 		if(StringUtils.isNotBlank(rows))
    50. 			this.setRows(Integer.valueOf(rows));
    51. 	}
    52.  
    53. 	public void setPagination(String pagination) {
    54. //		只有在前台jsp填写了pagination=false，才代表不分页
    55. 		if(StringUtils.isNotBlank(pagination))
    56. 			this.setPagination(!"false".equals(pagination));
    57. 	}
    58.  
    59.  
    60. 	public String getUrl() {
    61. 		return url;
    62. 	}
    63.  
    64. 	public void setUrl(String url) {
    65. 		this.url = url;
    66. 	}
    67.  
    68. 	public Map getParamMap() {
    69. 		return paramMap;
    70. 	}
    71.  
    72. 	public void setParamMap(Map paramMap) {
    73. 		this.paramMap = paramMap;
    74. 	}
    75.  
    76.  
    77.  
    78. 	public PageBean() {
    79. 		super();
    80. 	}
    81.  
    82. 	public int getPage() {
    83. 		return page;
    84. 	}
    85.  
    86. 	public void setPage(int page) {
    87. 		this.page = page;
    88. 	}
    89.  
    90. 	public int getRows() {
    91. 		return rows;
    92. 	}
    93.  
    94. 	public void setRows(int rows) {
    95. 		this.rows = rows;
    96. 	}
    97.  
    98. 	public int getTotal() {
    99. 		return total;
    100. 	}
    101.  
    102. 	public void setTotal(int total) {
    103. 		this.total = total;
    104. 	}
    105.  
    106. 	public void setTotal(String total) {
    107. 		this.total = Integer.parseInt(total);
    108. 	}
    109.  
    110. 	public boolean isPagination() {
    111. 		return pagination;
    112. 	}
    113.  
    114. 	public void setPagination(boolean pagination) {
    115. 		this.pagination = pagination;
    116. 	}
    117.  
    118. 	/**
    119. 	 * 获得起始记录的下标
    120. 	 * 
    121. 	 * @return
    122. 	 */
    123. 	public int getStartIndex() {
    124. 		return (this.page - 1) * this.rows;
    125. 	}
    126. 	
    127. 	/**
    128. 	 * 最大页
    129. 	 * @return
    130. 	 */
    131. 	public int maxPage() {
    132. //		total % rows == 0 ? total / rows : total / rows +1
    133. 		return this.total % this.rows == 0 ? this.total / this.rows : this.total / this.rows + 1;
    134. 	}
    135. 	
    136. 	/**
    137. 	 * 下一页
    138. 	 * @return
    139. 	 */
    140. 	public int nextPage() {
    141. //		如果当前页小于最大页，那就下一页为当前页+1；如果不小于，说明当前页就是最大页，那就无需+1
    142. 		return this.page < this.maxPage() ? this.page + 1 : this.page;
    143. 	}
    144. 	
    145. 	/**
    146. 	 * 上一页
    147. 	 * @return
    148. 	 */
    149. 	public int previousPage() {
    150. 		return this.page > 1 ? this.page - 1 : this.page;
    151. 	}
    152.  
    153. 	@Override
    154. 	public String toString() {
    155. 		return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", pagination=" + pagination + "]";
    156. 	}
    157.  
    158. }

     StringUtils 

    1. package com.cdl.springboot04.util;
    2.  
    3. public class StringUtils {
    4. 	// 私有的构造方法，保护此类不能在外部实例化
    5. 	private StringUtils() {
    6. 	}
    7.  
    8. 	/**
    9. 	 * 如果字符串等于null或去空格后等于""，则返回true，否则返回false
    10. 	 * 
    11. 	 * @param s
    12. 	 * @return
    13. 	 */
    14. 	public static boolean isBlank(String s) {
    15. 		boolean b = false;
    16. 		if (null == s || s.trim().equals("")) {
    17. 			b = true;
    18. 		}
    19. 		return b;
    20. 	}
    21. 	
    22. 	/**
    23. 	 * 如果字符串不等于null或去空格后不等于""，则返回true，否则返回false
    24. 	 * 
    25. 	 * @param s
    26. 	 * @return
    27. 	 */
    28. 	public static boolean isNotBlank(String s) {
    29. 		return !isBlank(s);
    30. 	}
    31.  
    32. }

    对应接口的实现类 

     ClazzBizImpl 

    1. package com.cdl.springboot04.biz.impl;
    2.  
    3. import com.cdl.springboot04.biz.ClazzBiz;
    4. import com.cdl.springboot04.mapper.ClazzMapper;
    5. import com.cdl.springboot04.model.Clazz;
    6. import com.cdl.springboot04.util.PageBean;
    7. import org.springframework.beans.factory.annotation.Autowired;
    8. import org.springframework.stereotype.Service;
    9.  
    10. import java.util.List;
    11. import java.util.Map;
    12.  
    13. /**
    14.  * @author小李飞刀
    15.  * @site www.javaxl.com
    16.  * @company xxx公司
    17.  * @create  2022-08-17 15:13
    18.  */
    19. @Service
    20. public class ClazzBizImpl implements ClazzBiz {
    21.     @Autowired
    22.     private ClazzMapper clazzMapper;
    23.     @Override
    24.     public int deleteByPrimaryKey(Integer cid) {
    25.        //  System.out.println("不做任何操作...");
    26.        return clazzMapper.deleteByPrimaryKey(cid);
    27.        //  return 0;
    28.     }
    29.  
    30.     @Override
    31.     public int insert(Clazz record) {
    32.         return clazzMapper.insert(record);
    33.     }
    34.  
    35.     @Override
    36.     public int insertSelective(Clazz record) {
    37.         return clazzMapper.insertSelective(record);
    38.     }
    39.  
    40.     @Override
    41.     public Clazz selectByPrimaryKey(Integer cid) {
    42.         return clazzMapper.selectByPrimaryKey(cid);
    43.     }
    44.  
    45.     @Override
    46.     public int updateByPrimaryKeySelective(Clazz record) {
    47.         return clazzMapper.updateByPrimaryKeySelective(record);
    48.     }
    49.  
    50.     @Override
    51.     public int updateByPrimaryKey(Clazz record) {
    52.         return clazzMapper.updateByPrimaryKey(record);
    53.     }
    54.  
    55.     @Override
    56.     public List listPager(Clazz clazz, PageBean pageBean) {
    57.         return clazzMapper.listPager(clazz);
    58.     }
    59.  
    60.     @Override
    61.     public List listMapPager(Clazz clazz, PageBean pageBean) {
    62.         if(true)
    63.             throw new RuntimeException("查询班级信息异常，异常存在于ClazzBizImpl.list。。。。");
    64.         return clazzMapper.listMapPager(clazz);
    65.     }
    66. }

    整合aop pageHelper插件

    导入所需要的pom依赖

    1.  
    2.         <dependency>
    3.             <groupId>org.springframeworkgroupId>
    4.             <artifactId>spring-aspectsartifactId>
    5.             <version>5.0.2.RELEASEversion>
    6.         dependency>
    7.         
    8.         <dependency>
    9.             <groupId>com.github.pagehelpergroupId>
    10.             <artifactId>pagehelper-spring-boot-starterartifactId>
    11.             <version>1.2.3version>
    12.         dependency>

     PagerAspect 

    1. package com.cdl.springboot04.aspect;
    2.  
    3. import com.cdl.springboot04.util.PageBean;
    4. import com.github.pagehelper.PageHelper;
    5. import com.github.pagehelper.PageInfo;
    6. import org.aspectj.lang.ProceedingJoinPoint;
    7. import org.aspectj.lang.annotation.Around;
    8. import org.aspectj.lang.annotation.Aspect;
    9. import org.springframework.stereotype.Component;
    10.  
    11. import java.util.List;
    12.  
    13. /**
    14.  * @author小李飞刀
    15.  * @site www.javaxl.com
    16.  * @company xxx公司
    17.  * @create  2022-08-12 16:32
    18.  */
    19. @Component
    20. @Aspect
    21. public class PagerAspect {
    22.  
    23.     /**
    24.      * *：返回值类型
    25.      * *..：无限包
    26.      * *Service：以Service结尾接口名
    27.      * *Pager：以Pager方法
    28.      * 只要同时匹配上诉四个条件，就会被列为目标对象
    29.      * 上述配置要生效，代理注解不能少
    30.      * @param args
    31.      * @return
    32.      * @throws Throwable
    33.      */
    34.     @Around("execution(* *..*Biz.*Pager(..))")
    35.     public Object invoke(ProceedingJoinPoint args) throws Throwable {
    36.         Object[] params = args.getArgs();
    37.         PageBean pageBean = null;
    38.         for (Object param : params) {
    39.             if(param instanceof PageBean){
    40.                 pageBean = (PageBean)param;
    41.                 break;
    42.             }
    43.         }
    44.  
    45.         if(pageBean != null && pageBean.isPagination())
    46.             PageHelper.startPage(pageBean.getPage(),pageBean.getRows());
    47.  
    48. //        执行目标方法
    49.         Object list = args.proceed(params);
    50.  
    51.         if(null != pageBean && pageBean.isPagination()){
    52.             PageInfo pageInfo = new PageInfo((List) list);
    53.             pageBean.setTotal(pageInfo.getTotal()+"");
    54.         }
    55.         return list;
    56.     }
    57.  
    58.  
    59. }

     application.yml中添加该配置

    pagehelper:
      reasonable: true
      supportMethodsArguments: true
      page-size-zero: true
      helper-dialect: mysql

     application.yml

    1. mybatis:
    2.     mapper-locations: classpath:mappers/*xml
    3.     type-aliases-package: com.cdl.springboot04.model
    4. server:
    5.     port: 8080
    6.     servlet:
    7.         context-path: /springboot04
    8. spring:
    9.     application:
    10.         name: springboot04
    11.     datasource:
    12.         driver-class-name: com.mysql.jdbc.Driver
    13.         name: defaultDataSource
    14.         password: 123456
    15.         url: jdbc:mysql://localhost:3306/mysql?useUnicode=true&characterEncoding=UTF-8&useSSL=false
    16.         username: root
    17.     freemarker:
    18.         cache: false
    19.         charset: utf-8
    20.         expose-request-attributes: true
    21.         expose-session-attributes: true
    22.         suffix: .ftl
    23.         template-loader-path: classpath:/templates/
    24. #    resources:
    25. #       static-locations: classpath:/static/# 应用服务 WEB 访问端口
    26.     mvc:
    27.         static-path-pattern: classpath:/static/
    28. pagehelper:
    29.     reasonable: true
    30.     supportMethodsArguments: true
    31.     page-size-zero: true
    32.     helper-dialect: mysql

     此时就具备了分页的功能

    jsp->freemaker

     将对应的clzList.jsp和clzEdit.jsp复制放入clz里面 参考得出clzList.ftl和clzEdit.ftl

    clzList.jsp

    1. <%@ page language="java" contentType="text/html; charset=UTF-8"
    2.          pageEncoding="UTF-8"%>
    3. <%@ taglib uri="http://jsp.veryedu.cn" prefix="z"%>
    4. <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    5. html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    6. <html>
    7. <head>
    8.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    9.     <link
    10.             href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
    11.             rel="stylesheet">
    12.     <script
    13.             src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js">script>
    14.     <title>博客列表title>
    15.     <style type="text/css">
    16.         .page-item input {
    17.             padding: 0;
    18.             width: 40px;
    19.             height: 100%;
    20.             text-align: center;
    21.             margin: 0 6px;
    22.         }
    23.  
    24.         .page-item input, .page-item b {
    25.             line-height: 38px;
    26.             float: left;
    27.             font-weight: 400;
    28.         }
    29.  
    30.         .page-item.go-input {
    31.             margin: 0 10px;
    32.         }
    33.     style>
    34. head>
    35. <body>
    36. <form class="form-inline"
    37.       action="${pageContext.request.contextPath }/clz/list" method="post">
    38.     <div class="form-group mb-2">
    39.         <input type="text" class="form-control-plaintext" name="cname"
    40.                placeholder="请输入班级名称">
    41.     div>
    42.     <button type="submit" class="btn btn-primary mb-2">查询button>
    43.     <a class="btn btn-primary mb-2" href="${pageContext.request.contextPath }/clz/toEdit">新增a>
    44. form>
    45.  
    46. <table class="table table-striped bg-success">
    47.     <thead>
    48.     <tr>
    49.         <th scope="col">IDth>
    50.         <th scope="col">班级名称th>
    51.         <th scope="col">指导老师th>
    52.         <th scope="col">班级相册th>
    53.         <th scope="col">操作th>
    54.     tr>
    55.     thead>
    56.     <tbody>
    57.     <c:forEach  var="b" items="${lst }">
    58.         <tr>
    59.             <td>${b.cid }td>
    60.             <td>${b.cname }td>
    61.             <td>${b.cteacher }td>
    62.             <td>
    63.                 <img src="${pageContext.request.contextPath }${b.pic }" style="height: 100px;width: 100px;" />
    64.             td>
    65.             <td>
    66.                 <a href="${pageContext.request.contextPath }/clz/toEdit?cid=${b.cid}">修改a>
    67.                 <a href="${pageContext.request.contextPath }/clz/del?cid=${b.cid}">删除a>
    68.                 <a href="${pageContext.request.contextPath }/clzUpload.jsp?cid=${b.cid}">上传图片a>
    69.                 <a href="${pageContext.request.contextPath }/clz/download?cid=${b.cid}">下载图片a>
    70.             td>
    71.         tr>
    72.     c:forEach>
    73.     tbody>
    74. table>
    76. <z:page pageBean="${pageBean }">z:page>
    77.  
    78. body>
    79. html>

    clzEdit.jsp

    1. <%@ page language="java" contentType="text/html; charset=UTF-8"
    2.          pageEncoding="UTF-8"%>
    3. html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    4. <html>
    5. <head>
    6.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    7.     <title>博客的编辑界面title>
    8. head>
    9. <body>
    10. <%--<form action="${pageContext.request.contextPath }/clz/${empty b ? 'add' : 'edit'}" method="post">--%>
    11. <form action="${pageContext.request.contextPath }/clz/${empty b ? 'valiAdd' : 'edit'}" method="post">
    12.     cid:<input type="text" name="cid" value="${b.cid }"><span style="color: red;">${msg.cid}span><br>
    13.     cname:<input type="text" name="cname" value="${b.cname }"><span style="color: red;">${msg.cname}span><br>
    14.     cteacher:<input type="text" name="cteacher" value="${b.cteacher }"><span style="color: red;">${msg.cteacher}span><br>
    15.     <input type="submit">
    16. form>
    17. body>
    18. html>

    clzList.ftl

    1. html>
    2. <html lang="en">
    3. <head>
    4.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    5.     <link
    6.             href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
    7.             rel="stylesheet">
    8.     <script
    9.             src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js">script>
    10.     <title>班级列表title>
    11.     <style type="text/css">
    12.         .page-item input {
    13.             padding: 0;
    14.             width: 40px;
    15.             height: 100%;
    16.             text-align: center;
    17.             margin: 0 6px;
    18.         }
    19.  
    20.         .page-item input, .page-item b {
    21.             line-height: 38px;
    22.             float: left;
    23.             font-weight: 400;
    24.         }
    25.  
    26.         .page-item.go-input {
    27.             margin: 0 10px;
    28.         }
    29.     style>
    30. head>
    31. <body>
    32. <#include "/common.ftl">
    33. <#--查询的条件框-->
    34. <form class="form-inline"
    35.       action="${ctx }/clz/list" method="post">
    36.     <div class="form-group mb-2">
    37.         <input type="text" class="form-control-plaintext" name="cname"
    38.                placeholder="请输入班级名称">
    39.     div>
    40.     <button type="submit" class="btn btn-primary mb-2">查询button>
    41.     <a class="btn btn-primary mb-2" href="${ctx }/clz/toEdit">新增a>
    42. form>
    43. <#--数据展示表格-->
    44. <table class="table table-striped bg-success">
    45.     <thead>
    46.     <tr>
    47.         <th scope="col">IDth>
    48.         <th scope="col">班级名称th>
    49.         <th scope="col">指导老师th>
    50.         <th scope="col">操作th>
    51.     tr>
    52.     thead>
    53.     <tbody>
    54.     <#list lst as b>
    55.         <tr>
    56.             <td>${b.cid !}td>
    57.             <td>${b.cname !}td>
    58.             <td>${b.cteacher !}td>
    59.             <td>
    60.                 <a href="${ctx }/clz/toEdit?cid=${b.cid}">修改a>
    61.                 <a href="${ctx }/clz/del?cid=${b.cid}">删除a>
    62.             td>
    63.         tr>
    64.     
    65.     tbody>
    66. table>
    67. <#--jsp是借助助手类，而这里是Freemarker，没有jsp相关依赖-->
    68. ${pagestr !}
    69. body>
    70. html>

    clzEdit.ftl

    1. html>
    2. <html lang="en">
    3. <head>
    4.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    5.     <title>班级的编辑界面title>
    6. head>
    7. <body>
    8. <#include "/common.ftl">
    9. <#if b??>
    10.     <#--修改-->
    11.     <form action="${ctx }/clz/edit" method="post">
    12.         cid:<input type="text" name="cid" value="${b.cid !}"><br>
    13.         cname:<input type="text" name="cname" value="${b.cname !}"><br>
    14.         cteacher:<input type="text" name="cteacher" value="${b.cteacher !}"><br>
    15.         <input type="submit">
    16.     form>
    17. <#else>
    18.     <#--新增-->
    19.     <form action="${ctx }/clz/add" method="post">
    20.         cid:<input type="text" name="cid" value=""><br>
    21.         cname:<input type="text" name="cname" value=""><br>
    22.         cteacher:<input type="text" name="cteacher" value=""><br>
    23.         <input type="submit">
    24.     form>
    26. body>
    27. html>

    因为新建了clz的包，所以业务逻辑层要修改

    ClazzController 

    1. package com.cdl.springboot04.controller;
    2.  
    3. import com.cdl.springboot04.biz.ClazzBiz;
    4. import com.cdl.springboot04.model.Clazz;
    5. import com.cdl.springboot04.util.PageBean;
    6. import org.springframework.beans.factory.annotation.Autowired;
    7. import org.springframework.stereotype.Controller;
    8. import org.springframework.validation.BindingResult;
    9. import org.springframework.validation.FieldError;
    10. import org.springframework.web.bind.annotation.RequestMapping;
    11.  
    12. import javax.servlet.http.HttpServletRequest;
    13. import java.util.HashMap;
    14. import java.util.List;
    15. import java.util.Map;
    16.  
    17. /**
    18.  * @author小李飞刀
    19.  * @site www.javaxl.com
    20.  * @company xxx公司
    21.  * @create  2022-08-17 15:23
    22.  */
    23. @Controller
    24. @RequestMapping("/clz")
    25. public class ClazzController {
    26.     @Autowired
    27.     private ClazzBiz clazzBiz;
    28. //    list->clzList
    29. //    toList->重定向list->"redirect:/clz/list"
    30. //    toEdit->跳转到编辑界面->clzEdit
    31. //    Clazz : 以前是通过模型驱动接口封装，现在是直接在方法中接受参数即可
    32.     @RequestMapping("/list")
    33.     public String list(Clazz clazz, HttpServletRequest request){
    34.         System.out.println("我添加了 新的代码,终于不重启了....");
    35.         PageBean pageBean = new PageBean();
    36.         pageBean.setRequest(request);
    37.         List lst = this.clazzBiz.listPager(clazz, pageBean);
    38.         request.setAttribute("lst",lst);
    39.         request.setAttribute("pageBean",pageBean);
    40.         return "clz/clzList";
    41.     }
    42.  
    43.     @RequestMapping("/toEdit")
    44.     public String toEdit(Clazz clazz, HttpServletRequest request){
    45.         Integer cid = clazz.getCid();
    46. //        传递的id代表了修改，没传代表新增
    47.         if(cid != null){
    48.             List lst = this.clazzBiz.listPager(clazz, null);
    49.             request.setAttribute("b",lst.get(0));
    50.         }
    51.         return "clz/clzEdit";
    52.     }
    53.  
    54.     @RequestMapping("/add")
    55.     public String add(Clazz clazz){
    56.         this.clazzBiz.insertSelective(clazz);
    57.         return "redirect:/clz/list";
    58.     }
    59.  
    60.  
    61.     @RequestMapping("/edit")
    62.     public String edit(Clazz clazz){
    63.         this.clazzBiz.updateByPrimaryKeySelective(clazz);
    64.         return "redirect:/clz/list";
    65.     }
    66.  
    67.     @RequestMapping("/del")
    68.     public String del(Clazz clazz){
    69.         this.clazzBiz.deleteByPrimaryKey(clazz.getCid());
    70.         return "redirect:/clz/list";
    71.     }
    72.  
    73.  
    74. }

    测试一波：

    运行后台启动报错

     因为启动类没有开启扫描

    Springboot04Application 

    1. package com.cdl.springboot04;
    2.  
    3. import org.mybatis.spring.annotation.MapperScan;
    4. import org.springframework.boot.SpringApplication;
    5. import org.springframework.boot.autoconfigure.SpringBootApplication;
    6.  
    7. @MapperScan("com.cdl.springboot04.mapper")//扫描
    8. @EnableTransactionManagement//开启事务
    9. @SpringBootApplication
    10. public class Springboot04Application {
    11.  
    12.     public static void main(String[] args) {
    13.  
    14.         SpringApplication.run(Springboot04Application.class, args);
    15.     }
    16.  
    17. }

    后台启动成功

     前端页面访问成功

     模糊查询

     添加进application.yml

     

    logging:
    level:
        com.cdl.springboot04: debug

     application.yml

    1. mybatis:
    2.     mapper-locations: classpath:mappers/*xml
    3.     type-aliases-package: com.cdl.springboot04.model
    4. server:
    5.     port: 8080
    6.     servlet:
    7.         context-path: /springboot04
    8. spring:
    9.     application:
    10.         name: springboot04
    11.     datasource:
    12.         driver-class-name: com.mysql.jdbc.Driver
    13.         name: defaultDataSource
    14.         password: 123456
    15.         url: jdbc:mysql://localhost:3306/mysql?useUnicode=true&characterEncoding=UTF-8&useSSL=false
    16.         username: root
    17.     freemarker:
    18.         cache: false
    19.         charset: utf-8
    20.         expose-request-attributes: true
    21.         expose-session-attributes: true
    22.         suffix: .ftl
    23.         template-loader-path: classpath:/templates/
    24. #    resources:
    25. #       static-locations: classpath:/static/# 应用服务 WEB 访问端口
    26.     mvc:
    27.         static-path-pattern: classpath:/static/
    28. pagehelper:
    29.     reasonable: true
    30.     supportMethodsArguments: true
    31.     page-size-zero: true
    32.     helper-dialect: mysql
    33.     logging:
    34.         level:
    35.             com.cdl.springboot04: debug

    删除

     删除成功

     新增

     新增成功

     修改

     修改成功

     实现分页功能

    新建一个分页的工具类

    FreemarkerPageHelper 

    1. package com.cdl.springboot04.util;
    2.  
    3. import java.util.Map;
    4. import java.util.Map.Entry;
    5. import java.util.Set;
    6.  
    7. /**
    8.  * @author cdl
    9.  * @site www.cdl.com
    10.  * @create 2022-11-02 1:25
    11.  */
    12. public class FreemarkerPageHelper {
    13.  
    14.     public static String toHTML(PageBean pageBean) {
    15.         StringBuffer sb = new StringBuffer();
    16. //		隐藏的form表单---这个就是上一次请求下次重新发的奥义所在
    17. //		上一次请求的URL
    18.         sb.append("
      ");
    19.         sb.append("	");
    20. //		上一次请求的参数
    21.         Map paramMap = pageBean.getParamMap();
    22.         if(paramMap != null && paramMap.size() > 0) {
    23.             Set> entrySet = paramMap.entrySet();
    24.             for (Entry entry : entrySet) {
    25. //				参数名
    26.                 String key = entry.getKey();
    27. //				参数值
    28.                 for (String value : entry.getValue()) {
    29. //					上一次请求的参数，再一次组装成了新的Form表单
    30. //					注意：page参数每次都会提交，我们需要避免
    31.                     if(!"page".equals(key)) {
    32.                         sb.append("	");
    33.                     }
    34.                 }
    35.             }
    36.         }
    37.         sb.append("");
    38.  
    39. //		分页条
    40.         sb.append("
        ");
    41.         sb.append("	
    42. );
  • sb.append(" href='javascript:gotoPage(1)'>首页
    • ");
  • sb.append("
  • );
  • sb.append(" href='javascript:gotoPage("+pageBean.previousPage()+")'><
    • ");// less than 小于号
  • // sb.append("
  • 1
    • ");
  • // sb.append("
  • 2
    • ");
  • sb.append("
  • "+pageBean.getPage()+"
    • ");
  • sb.append("
  • >
    • ");
  • sb.append("
  • 尾页
    • ");
  • sb.append("
  • 到第);
  • sb.append(" type='text' id='skipPage' name='' />页
    • ");
  • sb.append("
  • );
  • sb.append(" href='javascript:skipPage()'>确定
    • ");
  • sb.append("
  • 共"+pageBean.getTotal()+"条
    • ");
  • sb.append("");
  • // 分页执行的JS代码
  • sb.append("");
  • return sb.toString();
  • }
  • }

    •  ClazzController 

    添加使用分页工具类的代码

    1. package com.cdl.springboot04.controller;
    2.  
    3. import com.cdl.springboot04.biz.ClazzBiz;
    4. import com.cdl.springboot04.model.Clazz;
    5. import com.cdl.springboot04.util.FreemarkerPageHelper;
    6. import com.cdl.springboot04.util.PageBean;
    7. import org.springframework.beans.factory.annotation.Autowired;
    8. import org.springframework.stereotype.Controller;
    9. import org.springframework.validation.BindingResult;
    10. import org.springframework.validation.FieldError;
    11. import org.springframework.web.bind.annotation.RequestMapping;
    12.  
    13. import javax.servlet.http.HttpServletRequest;
    14. import java.util.HashMap;
    15. import java.util.List;
    16. import java.util.Map;
    17.  
    18. /**
    19.  * @author小李飞刀
    20.  * @site www.javaxl.com
    21.  * @company xxx公司
    22.  * @create  2022-08-17 15:23
    23.  */
    24. @Controller
    25. @RequestMapping("/clz")
    26. public class ClazzController {
    27.     @Autowired
    28.     private ClazzBiz clazzBiz;
    29. //    list->clzList
    30. //    toList->重定向list->"redirect:/clz/list"
    31. //    toEdit->跳转到编辑界面->clzEdit
    32. //    Clazz : 以前是通过模型驱动接口封装，现在是直接在方法中接受参数即可
    33.     @RequestMapping("/list")
    34.     public String list(Clazz clazz, HttpServletRequest request){
    35.         System.out.println("我添加了 新的代码,终于不重启了....");
    36.         PageBean pageBean = new PageBean();
    37.         pageBean.setRequest(request);
    38.         List lst = this.clazzBiz.listPager(clazz, pageBean);
    39.         request.setAttribute("lst",lst);
    40.         request.setAttribute("pageBean",pageBean);
    41.         //分页
    42.         request.setAttribute("pagestr", FreemarkerPageHelper.toHTML(pageBean));
    43.         return "clz/clzList";
    44.     }
    45.  
    46.     @RequestMapping("/toEdit")
    47.     public String toEdit(Clazz clazz, HttpServletRequest request){
    48.         Integer cid = clazz.getCid();
    49. //        传递的id代表了修改，没传代表新增
    50.         if(cid != null){
    51.             List lst = this.clazzBiz.listPager(clazz, null);
    52.             request.setAttribute("b",lst.get(0));
    53.         }
    54.         return "clz/clzEdit";
    55.     }
    56.  
    57.     @RequestMapping("/add")
    58.     public String add(Clazz clazz){
    59.         this.clazzBiz.insertSelective(clazz);
    60.         return "redirect:/clz/list";
    61.     }
    62.  
    63.  
    64.     @RequestMapping("/edit")
    65.     public String edit(Clazz clazz){
    66.         this.clazzBiz.updateByPrimaryKeySelective(clazz);
    67.         return "redirect:/clz/list";
    68.     }
    69.  
    70.     @RequestMapping("/del")
    71.     public String del(Clazz clazz){
    72.         this.clazzBiz.deleteByPrimaryKey(clazz.getCid());
    73.         return "redirect:/clz/list";
    74.     }
    75.  
    76.  
    77. }

    成功

     

     注意：

     

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  • 原文地址：https://blog.csdn.net/weixin_62735525/article/details/127638213