springBoot的分页插件_springboot分页插件

目录

1、加入依赖

2、配置分页插件

3、使用分页插件

1、加入依赖

<!--        分页插件-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.3.0</version>
        </dependency>

2、配置分页插件

#指定数据库
pagehelper.helper-dialect=mysql
#是否启用分页合理化，当pagenum<1时，自动查寻第一页数据，当pegenum>pages时，最后查询最后一页数据
pagehelper.reasonable=true
#支持分页参数写在mapper接口的方法里（方法中传参）
pagehelper.support-methods-arguments=true
pagehelper.params=count=countSql

         注：如果报循环依赖的错误：

┌──->──┐
|  com.github.pagehelper.autoconfigure.PageHelperAutoConfiguration
└──<-──┘
Action:

Relying upon circular references is discouraged and they are prohibited by default. Update your application to remove the dependency cycle between beans. As a last resort, it may be possible to break the cycle automatically by setting spring.main.allow-circular-references to true.

在配置文件中加入解决循环依赖的配置

#解决循环依赖
spring.main.allow-circular-references=true

3、使用分页插件

//方法中的pageNum和pageSize两个参数，在dao和service层的方法中无需传参    
    @GetMapping("/user")
    public String queryPageUser(@RequestParam(value = "pageNum",defaultValue = "1",required = false) Integer pageNum,
                            @RequestParam(value = "pageSize",defaultValue = "2",required = false) Integer pageSize) throws JsonProcessingException {
        PageHelper.startPage(pageNum,pageSize);
        List<User> list = userService.queryPageUser();
        PageInfo<User> userPageInfo = new PageInfo<>(list);
        String s = objectMapper.writeValueAsString(userPageInfo);
        return s;
    }