添加分页插件

@Configuration
@ConditionalOnClass(value = {PaginationInnerInterceptor.class})
public class MybatisPlusConfig {
    /**
     * 分页插件
     * @return
     */
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor() {
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
        return interceptor;
    }
}

Dao接口

 IPage<Announcement> querryAllAnnouncement(IPage<Announcement> page);

 <select id="querryAllAnnouncement" resultType="Announcement">
    select announcement_id, context, title, `type`, `type_name`, create_time
    from announcement
             left join announcement_type on announcement.type = announcement_type.type_id
    order by announcement.announcement_id desc
</select>

调用

 public AnnouncementVO listAnnouncements(int pageIndex, int pageSize) {
    IPage<Announcement> page = new Page<>(pageIndex, pageSize);
    IPage<Announcement> list = announcementDao.querryAllAnnouncement(page);

    AnnouncementVO announcementVO = new AnnouncementVO();
    announcementVO.setPages(list.getPages());
    announcementVO.setTotal(list.getTotal());
    announcementVO.setPageSize(pageSize);
    announcementVO.setAnnouncements(list.getRecords());

    return announcementVO;
}