商品评价

需求分析

• 好评度
• 按照评价等级可以过滤显示评价内容
• 评价内容里面的用户名有一个脱敏显示
• 评价有分页
• 默认显示的是所有评价

这里使用一张评价表就可以搞定了

注意：这里额外保存了 商品规则名称 和 商品名称，商品信息有可能会被更改，所以这里额外保存了

接口实现

这里总共会提供两个接口：

• 查询商品评价等级：统计不同评价等级的评价数量查询出来
• 查询商品评论：查询不同评价等级的使用一个接口进行条件查询即可

查询商品评价等级接口

    @Transactional(propagation = Propagation.SUPPORTS)
    @Override
    public CommentLevelCountsVO queryCommentCounts(String itemId) {
        Integer goodCounts = getCommentCounts(itemId, CommentLevel.GOOD.type);
        Integer normalCounts = getCommentCounts(itemId, CommentLevel.NORMAL.type);
        Integer badCounts = getCommentCounts(itemId, CommentLevel.BAD.type);
        Integer totalCounts = goodCounts + normalCounts + badCounts;

        CommentLevelCountsVO countsVO = new CommentLevelCountsVO();
        countsVO.setTotalCounts(totalCounts);
        countsVO.setGoodCounts(goodCounts);
        countsVO.setNormalCounts(normalCounts);
        countsVO.setBadCounts(badCounts);

        return countsVO;
    }

使用了 VO 返回 3 个等级的评价数量

    @ApiOperation(value = "查询商品评价等级", notes = "查询商品评价等级", httpMethod = "GET")
    @GetMapping("/commentLevel")
    public JSONResult commentLevel(
            @ApiParam(name = "itemId", value = "商品 id", required = true)
            @RequestParam String itemId) {

        if (StringUtils.isBlank(itemId)) {
            return JSONResult.errorMsg(null);
        }

        CommentLevelCountsVO countsVO = itemService.queryCommentCounts(itemId);

        return JSONResult.ok(countsVO);
    }

使用 pagehelper 实现分页查询

引入依赖

<!--pagehelper-->
<dependency>
  <groupId>com.github.pagehelper</groupId>
  <artifactId>pagehelper-spring-boot-starter</artifactId>
  <version>1.2.3</version>
</dependency>

配置

# 分页插件配置
pagehelper:
  helperDialect: mysql
  supportMethodsArguments: true

使用分页插件，在查询前使用分页插件，原理：统一拦截 sql，为其提供分页功能

/**
* page: 第几页 
* pageSize: 每页显示条数 
*/ 
PageHelper.startPage(page, pageSize);

分页数据封装到 PagedGridResult.java 传给前端

// 这一句和 PageHelper.startPage(page, pageSize); 是配套使用的
PageInfo<?> pageList = new PageInfo<>(list); 

// 后面的是自定义响应对象
PagedGridResult grid = new PagedGridResult();
grid.setPage(page);
grid.setRows(list); 
grid.setTotal(pageList.getPages()); 
grid.setRecords(pageList.getTotal());

查询商品评论接口

public interface ItemsMapperCustom {
    List<ItemCommentVO> queryItemComments(@Param("paramsMap") Map<String, Object> map);
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="cn.mrcode.foodiedev.mapper.ItemsMapperCustom">
    <select id="queryItemComments" parameterType="Map" resultType="cn.mrcode.foodiedev.pojo.vo.ItemCommentVO">
        SELECT ic.comment_level as commentLevel,
                ic.content       as content,
                ic.sepc_name     as specName,
                ic.created_time  as createdTime,
                u.face           as userFace,
                u.nickname       as nickname
        FROM items_comments ic
            LEFT JOIN users u ON ic.user_id = u.id
        WHERE ic.item_id = #{paramsMap.itemId}
        <if test=" paramsMap.level != null and paramsMap.level != '' ">
            AND ic.comment_level = #{paramsMap.level}
        </if>
    </select>
</mapper>

评价表与用户表进行了一个关联查询，查询评价信息和谁评价的信息

service

    @Transactional(propagation = Propagation.SUPPORTS)
    @Override
    public PagedGridResult queryPagedComments(String itemId,
                                              Integer level,
                                              Integer page,
                                              Integer pageSize) {

        Map<String, Object> map = new HashMap<>();
        map.put("itemId", itemId);
        map.put("level", level);

        // mybatis-pagehelper

        /**
         * page: 第几页
         * pageSize: 每页显示条数
         */
        PageHelper.startPage(page, pageSize);

        List<ItemCommentVO> list = itemsMapperCustom.queryItemComments(map);
        for (ItemCommentVO vo : list) {
            // 将昵称进行脱敏处理
            // test -> t**t
            vo.setNickname(DesensitizationUtil.commonDisplay(vo.getNickname()));
        }

        return setterPagedGrid(list, page);
    }

    /**
     * 通用的转成我们自己的 pageResult 方法
     *
     * @param list
     * @param page
     * @return
     */
    private PagedGridResult setterPagedGrid(List<?> list, Integer page) {
        PageInfo<?> pageList = new PageInfo<>(list);
        PagedGridResult grid = new PagedGridResult();
        grid.setPage(page);
        grid.setRows(list);
        grid.setTotal(pageList.getPages());
        grid.setRecords(pageList.getTotal());
        return grid;
    }

/**
 * @Description: 用来返回分页 Grid 的数据格式
 */
public class PagedGridResult {

    private int page;            // 当前页数
    private int total;            // 总页数
    private long records;        // 总记录数
    private List<?> rows;        // 每行显示的内容

controller

    @ApiOperation(value = "查询商品评论", notes = "查询商品评论", httpMethod = "GET")
    @GetMapping("/comments")
    public JSONResult comments(
            @ApiParam(name = "itemId", value = "商品 id", required = true)
            @RequestParam String itemId,
            @ApiParam(name = "level", value = "评价等级", required = false)
            @RequestParam Integer level,
            @ApiParam(name = "page", value = "查询下一页的第几页", required = false)
            @RequestParam Integer page,
            @ApiParam(name = "pageSize", value = "分页的每一页显示的条数", required = false)
            @RequestParam Integer pageSize) {

        if (StringUtils.isBlank(itemId)) {
            return JSONResult.errorMsg(null);
        }

        if (page == null) {
            page = 1;
        }

        if (pageSize == null) {
            // 继承了 BaseController 中定义的评论默认分页数量
            pageSize = COMMON_PAGE_SIZE;
        }

        PagedGridResult grid = itemService.queryPagedComments(itemId,
                level,
                page,
                pageSize);

        return JSONResult.ok(grid);
    }

脱敏工具

package cn.mrcode.foodiedev.common.util;

import sun.applet.Main;

/**
 * 通用脱敏工具类
 * 可用于：
 * 用户名
 * 手机号
 * 邮箱
 * 地址等
 */
public class DesensitizationUtil {

    private static final int SIZE = 6;
    private static final String SYMBOL = "*";

    public static void main(String[] args) {
        String name = commonDisplay("慕课网");
        String mobile = commonDisplay("13900000000");
        String mail = commonDisplay("admin@imooc.com");
        String address = commonDisplay("北京大运河东路888号");

        System.out.println(name);
        System.out.println(mobile);
        System.out.println(mail);
        System.out.println(address);
    }

    /**
     * 通用脱敏方法
     *
     * @param value
     * @return
     */
    public static String commonDisplay(String value) {
        if (null == value || "".equals(value)) {
            return value;
        }
        int len = value.length();
        int pamaone = len / 2;
        int pamatwo = pamaone - 1;
        int pamathree = len % 2;
        StringBuilder stringBuilder = new StringBuilder();
        if (len <= 2) {
            if (pamathree == 1) {
                return SYMBOL;
            }
            stringBuilder.append(SYMBOL);
            stringBuilder.append(value.charAt(len - 1));
        } else {
            if (pamatwo <= 0) {
                stringBuilder.append(value.substring(0, 1));
                stringBuilder.append(SYMBOL);
                stringBuilder.append(value.substring(len - 1, len));

            } else if (pamatwo >= SIZE / 2 && SIZE + 1 != len) {
                int pamafive = (len - SIZE) / 2;
                stringBuilder.append(value.substring(0, pamafive));
                for (int i = 0; i < SIZE; i++) {
                    stringBuilder.append(SYMBOL);
                }
                if ((pamathree == 0 && SIZE / 2 == 0) || (pamathree != 0 && SIZE % 2 != 0)) {
                    stringBuilder.append(value.substring(len - pamafive, len));
                } else {
                    stringBuilder.append(value.substring(len - (pamafive + 1), len));
                }
            } else {
                int pamafour = len - 2;
                stringBuilder.append(value.substring(0, 1));
                for (int i = 0; i < pamafour; i++) {
                    stringBuilder.append(SYMBOL);
                }
                stringBuilder.append(value.substring(len - 1, len));
            }
        }
        return stringBuilder.toString();
    }

}