2、springBoot集成mybatis分页插件PageHelper-蒲公英云

2、springBoot集成mybatis分页插件PageHelper

前言

PageHelper是一款非常好用的分页插件，它和Mybatis工作在一起，可以大幅提升开发效率。PageHelper是通过Mybatis的拦截器插件原理实现的。

1、导入依赖

<!--分页插件-->
<dependency>
    <groupId>com.github.pagehelper</groupId>
    <artifactId>pagehelper</artifactId>
    <version>4.1.6</version>
</dependency>

2、启动加载PageHelperbean

package com.hlj.mybatisxml.pagehelper;
import com.github.pagehelper.PageHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.util.Properties;
/**
 * @Description
 * @Author HealerJean
 * @Date 2018/4/26  上午11:58.
 */
@Configuration
public class PageHelperConfiguration {
    private static final Logger log = LoggerFactory.getLogger(PageHelperConfiguration.class);
    @Bean
    public PageHelper pageHelper() {
        log.info("------Register MyBatis PageHelper");
        PageHelper pageHelper = new PageHelper();
        Properties p = new Properties();
        p.setProperty("offsetAsPageNum", "true");
        p.setProperty("rowBoundsWithCount", "true");
        p.setProperty("reasonable", "true");
        //通过设置pageSize=0或者RowBounds.limit = 0就会查询出全部的结果。
        p.setProperty("pageSizeZero", "true");
        pageHelper.setProperties(p);
        return pageHelper;
    }
}

3、直接分页开始

只要找出list来就可以进行分页了

@RestController
public class PageHelperController {
    @Resource
    private BasesetUserMapper basesetUserMapper;
    @RequestMapping(value = "page")
    public PageInfo<BasesetUser> queryAll(@RequestParam(value = "pageNum", required = false, defaultValue="1") Integer pageNum,
                                          @RequestParam(value = "pageSize", required = false, defaultValue="10") Integer pageSize) {
        //传入第几页和大小
        PageHelper.startPage(pageNum, pageSize);
        List<BasesetUser> list = basesetUserMapper.findMyall();
        PageInfo<BasesetUser> pageInfo = new PageInfo<BasesetUser>(list);
        return  pageInfo;
    }
}

4、测试

http://localhost:8888/page?pageNum=1&pageSize=2
{
    "pageNum": 1,
    "pageSize": 2,
    "size": 2,
    "orderBy": null,
    "startRow": 1,
    "endRow": 2,
    "total": 6,
    "pages": 3,
    "list": [{
        "id": 1,
        "username": "HealerJean",
        "password": "213456",
        "enable": 1
    }, {
        "id": 2,
        "username": "HealerJean",
        "password": "213456",
        "enable": 1
    }],
    "firstPage": 1,
    "prePage": 0,
    "nextPage": 2,
    "lastPage": 3,
    "isFirstPage": true,
    "isLastPage": false,
    "hasPreviousPage": false,
    "hasNextPage": true,
    "navigatePages": 8,
    "navigatepageNums": [1, 2, 3]
}

补充，代码中没有

1、通过分页对象进行前端传入

package com.appshike.admin.domain.page;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Getter;
import lombok.Setter;
import lombok.experimental.Accessors;
import springfox.documentation.annotations.ApiIgnore;
@Setter
@ApiModel("分页对象")
@Accessors(chain = true)
public class PageQuery {
    @ApiModelProperty(value = "开始页数，从1开始",example = "1", required = true,dataType = "java.lang.Integer")
    private Integer pageNum = 1;
    @ApiModelProperty(value = "每页数量",example = "20", required = true,dataType = "java.lang.Integer")
    private Integer pageSize = 20;
    @ApiModelProperty(hidden = true)
    public Integer getPageSize() {
        return pageSize == null ? 20 : pageSize;
    }
    public Integer getPageNum() {
        return pageNum == null ? 1 : pageNum;
    }
}

2、controller 其实和pageable是一样的了，是吧，但是这里根本不需要关注里面发生了什么只给一个list就可以了

@GetMapping("getCategoryTagList")
public Wrapper<?> getCategoryTagList(Long categoryId,Short classify, PageQuery pageQuery){
    Map<String,Object> query = new HashMap<String,Object>();
    query.put("categoryId", categoryId);
    query.put("classify", classify);
    PageInfo<TVideoCategoryTagVO> page = zqCategoryService.getCategoryTagList(query, pageQuery);
    return WrapMapper.ok(page);
}

3、service

@TargetDataSource(DataSource.ZUIQIANG)
@Override
public PageInfo<TVideoCategoryTagVO> getCategoryTagList(Map<String,Object> query, PageQuery pageQuery) {
    PageHelper.startPage(pageQuery.getPageNum(),pageQuery.getPageSize());
    List<TVideoCategoryTagVO> beanList = tVideoCategoryTagMapper.getList(query);
    return new PageInfo<>(beanList);
}