Springboot+PageHelper实现分页

喜欢ヅ旅行 2023-02-17 08:59 22阅读 0赞

1.工程搭建

*  导入依赖

<dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-jdbc</artifactId>
     </dependency>
     
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-web</artifactId>
     </dependency>
     
     <dependency>
         <groupId>mysql</groupId>
         <artifactId>mysql-connector-java</artifactId>
         <version>5.1.38</version>
     </dependency>
     
     <dependency>
         <groupId>tk.mybatis</groupId>
         <artifactId>mapper-spring-boot-starter</artifactId>
         <version>2.1.5</version>
     </dependency>
    
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-thymeleaf</artifactId>
     </dependency>
     
     <dependency>
         <groupId>com.alibaba</groupId>
         <artifactId>druid</artifactId>
         <version>1.1.10</version>
     </dependency>
     
     <dependency>
     <groupId>com.github.pagehelper</groupId>
     <artifactId>pagehelper-spring-boot-starter</artifactId>
     <version>1.2.10</version>
      </dependency>
      
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-devtools</artifactId>
         <scope>runtime</scope>
         <optional>true</optional>
     </dependency>
     
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-configuration-processor</artifactId>
         <optional>true</optional>
     </dependency>
     
     <dependency>
         <groupId>org.projectlombok</groupId>
         <artifactId>lombok</artifactId>
         <optional>true</optional>
     </dependency>

yml配置

spring:
      datasource:
        driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://localhost:3306/demo
        username: root
        password: 1234
      thymeleaf:
        cache: false  #关闭缓存
    #mybatis配置
    mybatis:
    #输出sql
      configuration:
        log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
      mapper-locations: mapper/*.xml #扫描mapper.xml文件
      type-aliases-package: com.whpu.pojo #javabean别名包扫描
    pagehelper:
      helper-dialect: mysql
      reasonable: true
      support-methods-arguments: true
      params: count=countSql

2. 业务代码

public interface UserMapperT extends Mapper<UserT> {
        //继承通用mapper
        //此处不需要任何方法
    }

user类

@Data
    @Table(name="user") //指向数据库表名
    public class UserT {
      @Id
      @KeySql(useGeneratedKeys = true)//表示在insert语句中，可将自动生成的主键id返回
      @GeneratedValue
        private Integer id;
        private String username;
        private String password;
    }

3.测试代码

@SpringBootTest
    class Springboot06ApplicationTests {
    @Autowired
    private UserMapperT userMapperT;
    @Test
    void test2() {
    //执行分页，pageNum： 当前页 ， pageSize ：每页显示数据条数
    PageHelper.startPage(1, 5);
    List<UserT> user=userMapperT.selectAll();
    //查询结果封装到pageinfo对象
    PageInfo<UserT> pageInfo =new PageInfo<>(user);
    System.out.println(pageInfo);
    }
    }

*   输出结果

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMjI0NjM4_size_16_color_FFFFFF_t_70][]

4.后台代码

@Autowired
    private UserMapperT userMapperT;
    @RequestMapping("lookuser")
    public ModelAndView lookuser(ModelAndView mv,
    @RequestParam(defaultValue = "1",value = "pageNum") Integer pageNum){
        //分页
        PageHelper.startPage(pageNum,5);
        //查询
        List<UserT> user=userMapperT.selectAll();
        //查询结果封装到pageinfo对象
        PageInfo<UserT> pageInfo =new PageInfo<>(user);
        mv.addObject("user",pageInfo);
        mv.setViewName("/select");
         return mv;
        }

其中：PageHelper.startPage(int PageNum,int PageSize):用来设置页面的位置和展示的数据条目数，我们设置每页展示5条数据。PageInfo用来封装页面信息，返回给前台界面。PageInfo中的一些我们需要用到的参数如下表：

<table style="width:500px;"> 
 <tbody> 
  <tr> 
   <td>PageInfo.list</td> 
   <td>结果集</td> 
  </tr> 
  <tr> 
   <td>PageInfo.pageNum</td> 
   <td>当前页码</td> 
  </tr> 
  <tr> 
   <td>PageInfo.pageSize</td> 
   <td>当前页面显示的数据条目</td> 
  </tr> 
  <tr> 
   <td>PageInfo.pages</td> 
   <td>总页数</td> 
  </tr> 
  <tr> 
   <td>PageInfo.total</td> 
   <td>数据的总条目数</td> 
  </tr> 
  <tr> 
   <td>PageInfo.prePage</td> 
   <td>上一页</td> 
  </tr> 
  <tr> 
   <td>PageInfo.nextPage</td> 
   <td>下一页</td> 
  </tr> 
  <tr> 
   <td>PageInfo.isFirstPage</td> 
   <td>是否为第一页</td> 
  </tr> 
  <tr> 
   <td>PageInfo.isLastPage</td> 
   <td>是否为最后一页</td> 
  </tr> 
  <tr> 
   <td>PageInfo.hasPreviousPage</td> 
   <td>是否有上一页</td> 
  </tr> 
  <tr> 
   <td>PageHelper.hasNextPage</td> 
   <td>是否有下一页</td> 
  </tr> 
 </tbody> 
</table>

5.前端代码

<!DOCTYPE html>
    <html lang="en" xmlns:th="http://www.thymeleaf.org">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <link rel="stylesheet" th:href="@{/amazeui/assets/css/amazeui.css}">
        <script th:src="@{/amazeui/assets/js/jquery.min.js}"></script>
        <script  th:src="@{/amazeui/assets/js/amazeui.js}"></script>
        <script th:src="@{/amazeui/pagination/amazeui-pagination.js}"></script>
    </head>
    <body>
    
    <div class="am-g">
    <div class="am-u-sm-5">
    
        <table class="am-table am-table-bordered  am-table-striped  am-table-centered am-table-hover am-table-compact">
            <h3 style="margin-bottom: 0px;margin-top: 30px">用户信息</h3>
            <tr>
                <td colspan ="4" >
                    <a class="am-btn am-btn-primary" style="float: right " th:href="@{/addtk(flag=1)}">添加</a>
                </td>
            </tr>
            <tr>
                <th>编号</th>
                <th>账号</th>
                <th>密码</th>
                <th>操作</th>
            </tr>
            
           <tr th:each="u:${user.list}" >
                <td th:text="${u.id}"></td>
                <td th:text="${u.username}"></td>
                <td th:text="${u.password}"></td>
                <td ><a class="am-btn am-btn-success" th:href="@{/updatetk(flag=1,id=${u.id})}">修改</a><a class="am-btn am-btn-danger" th:href="@{/deletetk(id=${u.id})}">删除</a></td>
            </tr>
        </table>
        <p>当前<span th:text="${user.pageNum}"></span>页，总<span th:text="${user.pages}"> </span>页，共<span th:text="${user.total}"></span>条数据</p>
        <a th:href="@{/lookuser}">首页</a>
        <a th:href="@{/lookuser(pageNum=${user.hasPreviousPage}?${user.prePage}:1)}">上一页</a>
        <a th:href="@{/lookuser(pageNum=${user.hasNextPage}?${user.nextPage}:${user.pages})}">下一页</a>
        <a th:href="@{/lookuser(pageNum=${user.pages})}">尾页</a>
    </div>
    </div>
    </body>
    </html>

*   结果

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMjI0NjM4_size_16_color_FFFFFF_t_70 1][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMjI0NjM4_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200613122702741.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMjI0NjM4,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMjI0NjM4_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20200613123028155.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMjI0NjM4,size_16,color_FFFFFF,t_70