实战SSM_O2O商铺_46【Redis缓存】头条信息+商铺目录Service层加入缓存

文章目录

• 概述
• HeadLineServiceImpl的改造
• ​
  • 代码
  • 单元测试
• ShopCategoryServiceImpl的改造
• ​
  • 代码
  • 单元测试
• Github地址

概述

根据数据的特点，不经常变动的数据 即时性要求没有那么高的读数据 为了减轻DB压力，我们可以将数据放到缓存中。

按照规划，目前我们需要将区域信息、商铺分类信息和头条信息放入到redis中。

实战SSM_O2O商铺_45【Redis缓存】配置Redis在Service层加入缓存中我们集成了Redis的配置，并使用AreaService来测试了配置的正确性。 接下来我们继续将商铺分类信息和头条信息放入到redis中。

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HeadLineServiceImpl的改造

代码

思路：根据mapper中不同的查询条件，在service层缓存不同的KEY，方便使用。

---

代码语言：javascript复制

package com.artisan.o2o.service.impl;

import java.util.ArrayList;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.artisan.o2o.cache.JedisUtil;
import com.artisan.o2o.dao.HeadLineDao;
import com.artisan.o2o.entity.HeadLine;
import com.artisan.o2o.service.HeadLineService;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;

@Service
public class HeadLineServiceImpl implements HeadLineService {

	private static final Logger logger = LoggerFactory.getLogger(HeadLineServiceImpl.class);

	@Autowired
	HeadLineDao headLineDao;

	@Autowired
	private JedisUtil.Strings jedisStrings;
	@Autowired
	private JedisUtil.Keys jedisKeys;

	@Override
	public List<HeadLine> queryHeadLineList(HeadLine headLineConditon) {
		List<HeadLine> headLineList = new ArrayList<HeadLine>();
		
		// 定义Key
		String key = "headline";
		// 定义jackson数据转换操作类
		ObjectMapper mapper = new ObjectMapper();
		
		// 根据mapper中的查询条件 拼装key
		// 根据不同的条件缓存不同的key值 这里有3种缓存 headline_0 headline_1 和 headline 方便管理员权限操作
		if (headLineConditon != null && headLineConditon.getEnableStatus() != null) {
			key = key   "_"   headLineConditon.getEnableStatus();
		}

		// 如果不存在，从数据库中获取数据，然后写入redis
		if(!jedisKeys.exists(key)){
			try {
				// 从DB中获取数据
				headLineList = headLineDao.selectHeadLineList(headLineConditon);
				// 将相关的实体类集合转换成string,存入redis里面对应的key中
				String jsonString = mapper.writeValueAsString(headLineList);
				jedisStrings.set(key, jsonString);
			} catch (JsonProcessingException e) {
				e.printStackTrace();
				logger.error("实体类集合转换string存入redis异常{}", e.getMessage());
			} catch (Exception e) {
				e.printStackTrace();
				logger.error("其他异常{}", e.getMessage());
			}
		} else {
			// 否则直接从redis中获取
			try {
				// 若存在，则直接从redis里面取出相应数据
				String jsonString = jedisStrings.get(key);
				// 指定要将string转换成的集合类型
				JavaType javaType = mapper.getTypeFactory().constructParametricType(ArrayList.class, HeadLine.class);
				// 将相关key对应的value里的的string转换成java对象的实体类集合
				headLineList = mapper.readValue(jsonString, javaType);
			} catch (Exception e) {
				e.printStackTrace();
				logger.error("异常{}", e.getMessage());
			}
		}
		return headLineList;
	}

}

单元测试

tb_head_line数据

代码语言：javascript复制

package com.artisan.o2o.service;

import java.util.List;

import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;

import com.artisan.o2o.BaseTest;
import com.artisan.o2o.entity.HeadLine;

public class HeadLineServiceTest extends BaseTest {

	@Autowired
	private HeadLineService headLineService;

	@Test
	public void testQueryHeadLineList() {
		HeadLine headLineConditon = new HeadLine();
		// 状态 0 不可用 1 可用
		headLineConditon.setEnableStatus(0);

		// 查询不可用的头条信息
		List<HeadLine> headLineList = headLineService.queryHeadLineList(headLineConditon);
		for (HeadLine headLine : headLineList) {
			System.out.println("0<<<<"   headLine);
		}

		// 查询可用的头条信息
		headLineConditon.setEnableStatus(1);
		headLineList = headLineService.queryHeadLineList(headLineConditon);
		for (HeadLine headLine : headLineList) {
			System.out.println("**------>"   headLine);
		}

		// 再次查询 状态为0 和 1的头条信息 ，确保从缓存中取数据
		// 查询不可用的头条信息
		headLineConditon.setEnableStatus(0);
		headLineList = headLineService.queryHeadLineList(headLineConditon);
		for (HeadLine headLine : headLineList) {
			System.out.println("0>>>>"   headLine);
		}

		// 查询可用的头条信息
		headLineConditon.setEnableStatus(1);
		headLineList = headLineService.queryHeadLineList(headLineConditon);
		for (HeadLine headLine : headLineList) {
			System.out.println("||------>"   headLine);
		}

	}
}

启动redis服务端，确保redis中无对应的数据，加入断点逐步调测观察。 单元测试后查看Redis中的数据

代码语言：javascript复制

127.0.0.1:6379> get headline_0
"[]"
127.0.0.1:6379> get headline_1
"[{"lineId":6,"lineName":"xe8xb4xadxe7x89xa9","lineLink":"xxx","lineImg":"\\upload\\item\\headtitle\\2018072520315746624.jpg","priority":99,"enableStatus":1,"createTime":null,"lastEditTime":null},{"lineId":2,"lineName":"xe5xaexb6xe5x85xb7","lineLink":"x","lineImg":"\\upload\\item\\headtitle\\2018072520371786788.jpg","priority":98,"enableStatus":1,"createTime":null,"lastEditTime":null},{"lineId":3,"lineName":"xe5x81xa5xe8xbaxab","lineLink":"xx","lineImg":"\\upload\\item\\headtitle\\2018072520393452772.jpg","priority":97,"enableStatus":1,"createTime":null,"lastEditTime":null},{"lineId":4,"lineName":"xe7xbex8exe5xaexb9","lineLink":"aa","lineImg":"\\upload\\item\\headtitle\\2018072520400198256.jpg","priority":96,"enableStatus":1,"createTime":null,"lastEditTime":null}]"
127.0.0.1:6379>

符合预期，测试通过。

---

ShopCategoryServiceImpl的改造

思路：根据mapper中不同的查询条件，在service层缓存不同的KEY，方便使用。

---

代码

代码语言：javascript复制

package com.artisan.o2o.service.impl;

import java.util.ArrayList;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.artisan.o2o.cache.JedisUtil;
import com.artisan.o2o.dao.ShopCategoryDao;
import com.artisan.o2o.entity.ShopCategory;
import com.artisan.o2o.service.ShopCategoryService;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;


@Service
public class ShopCategoryServiceImpl implements ShopCategoryService {
	
	private static final Logger logger = LoggerFactory.getLogger(ShopCategoryServiceImpl.class);
	
	@Autowired
	private ShopCategoryDao shopCategoryDao;
	
	@Autowired
	private JedisUtil.Keys jedisKeys;

	@Autowired
	private JedisUtil.Strings jedisStrings;

	@Override
	public List<ShopCategory> getShopCategoryList(ShopCategory shopCategory) {

		List<ShopCategory> shopCategoryList = new ArrayList<ShopCategory>();
		
		// 定义redis中key
		String key = "shopcategory";
		// 定义jackson数据转换操作类
		ObjectMapper mapper = new ObjectMapper();
		
		// 根据mapper中的查询条件，拼装shopcategory的key
		if (shopCategory == null) {
			// 查询条件为空，列出所有的首页大类，即parentId为空的店铺类别
			key = key   "_allfirstlevelshopcategory";
		} else if (shopCategory != null && shopCategory.getParent() != null && shopCategory.getParent().getShopCategoryId() != null) {
			// 列出某个parentId下面的所有子类
			key = key   "_parent"   shopCategory.getParent().getShopCategoryId();
		} else if (shopCategory != null) {
			// 列出所有的子类，不管属于哪个类
			key = key   "_allsecondlevelshopcategory";
		}

		// 如果缓存中不出在则从DB中查询并缓存到redis中
		if (!jedisKeys.exists(key)) {
			try {
				// 从DB中加载
				shopCategoryList = shopCategoryDao.queryShopCategoryList(shopCategory);
				// 将相关的实体类集合转换成string,存入redis里面对应的key中
				String jsonString = mapper.writeValueAsString(shopCategoryList);
				jedisStrings.set(key, jsonString);
			} catch (JsonProcessingException e) {
				e.printStackTrace();
				logger.error("实体类集合转换string存入redis异常{}", e.getMessage());
			} catch (Exception e) {
				e.printStackTrace();
				logger.error("其他异常{}", e.getMessage());
			}
		} else {
			// 否则直接从redis中获取
			try {
				String jsonString = jedisStrings.get(key);
				// 指定要将string转换成的集合类型
				JavaType javaType = mapper.getTypeFactory().constructParametricType(ArrayList.class, ShopCategory.class);
				// 将相关key对应的value里的的string转换成java对象的实体类集合
				shopCategoryList = mapper.readValue(jsonString, javaType);
			} catch (Exception e) {
				e.printStackTrace();
				logger.error("异常{}", e.getMessage());
			}
		}
		return shopCategoryList;
	}

}

---

单元测试

tb_shop_category 数据

代码语言：javascript复制

package com.artisan.o2o.service;

import java.util.List;

import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;

import com.artisan.o2o.BaseTest;
import com.artisan.o2o.entity.ShopCategory;

public class ShopServiceCategoryTest extends BaseTest {

	@Autowired
	ShopCategoryService shopCategoryService;

	@Test
	public void testQueryShopCategory() {
		
		List<ShopCategory> shopCategories;
		
		// 查询 ShopCategory为null的情况，即查询parent_id is null
		shopCategories = shopCategoryService.getShopCategoryList(null);
		for (ShopCategory shopCategory2 : shopCategories) {
			System.out.println("-----||"   shopCategory2);
		}

		// 查询 ShopCategory不为空的情况
		ShopCategory shopCategory = new ShopCategory();
		shopCategories = shopCategoryService.getShopCategoryList(shopCategory);
		for (ShopCategory shopCategory2 : shopCategories) {
			System.out.println("----->>"   shopCategory2);
		}

		// 查询对应父类下的目录
		ShopCategory parent = new ShopCategory();
		ShopCategory child = new ShopCategory();

		parent.setShopCategoryId(1L);
		child.setParent(parent);

		shopCategories = shopCategoryService.getShopCategoryList(child);
		for (ShopCategory shopCategory2 : shopCategories) {
			System.out.println("-----**"   shopCategory2);
		}

	}
}

运行两次，查看数据，符合预期

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Github地址

代码地址： https://github.com/yangshangwei/o2o

单元测试 缓存 云数据库Redis github git

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