摘要：
书面词典数据不会经常更新，但会经常查询。为了减少数据库链接的数量，请缓存项目全局变量中的内容，并提高方法查询速度importjavax。注释。后期构造；importjavax.annotation。预销毁；导入java.util。HashMap；导入java.util。列表导入java.util。地图；@堆肥
有写字典数据不会频繁更新，但是会频繁查询，想要减少数据库链接次数，把内容缓存到项目的全局变量中，提高方法查询速度
import javax.annotation.PostConstruct; import javax.annotation.PreDestroy; import java.util.HashMap; import java.util.List; import java.util.Map; @Component public class CodeCache { public static Map<String, TownNameDto> codeMap = new HashMap<String, TownNameDto>(); public static Map<String, CompanyModel> companyMap = new HashMap<String, CompanyModel>(); @Autowired private CityDao cityDao; @Autowired private CompanyDao companyDao; @PostConstruct public void init() { //系统启动中。。。加载codeMap List<TownNameDto> codeList = cityDao.selectCityNameAndCodeALL(); for (TownNameDto code : codeList) { codeMap.put(code.getTownCode() + code.getValue(), code); } List<CompanyModel> companyModels = companyDao.selectCompanies(); for (CompanyModel company : companyModels) { companyMap.put(company.getCode(), company); } } @PreDestroy public void destroy() { //系统运行结束 } @Scheduled(cron = "0 0 0/2 * * ?") public void testOne() { //每2小时执行一次缓存 init(); } }
使用：
//从缓存中获取城市； Map<String, TownNameDto> cityModelMap = CodeCache.codeMap; Map<String, CompanyModel> companyModelMap = CodeCache.companyMap;
转自：https://blog.csdn.net/Alice_qixin/article/details/101547611