【三层架构中使用策略模式，会使得三层架构中使用DAO层出现异常 _第三方API调用】

三层架构中使用策略模式，会使得三层架构中使用DAO层出现异常

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第三方API调用

详细描述

错误截图

源码

controller
	// 执行上传图片到阿里云
	@RequestMapping(value = "/uploadToAliYun", method = RequestMethod.POST)
	@ResponseBody
	public void userPhotoUploadToALiYun(@RequestParam("file") MultipartFile file, HttpServletRequest request,
										HttpServletResponse response) throws IOException {

		String result = null;
		// 使用策略模式
		UserPhotoUploadStrategyContext context = new UserPhotoUploadStrategyContext(new UserPhotoUploadToAliYunOSSImpl());
		context.executeUserPhotoUploadStrategy(request,response,file);

		// 上传文件
		// result = userPhotoUploadToAliYunOSS.userPhotoUploadToOSS(request, response, file);
		PrintWriter out = response.getWriter();
		out.print(result);
		out.flush();
		out.close();
		logger.info("上传阿里云返回结果：" + result );

	}


services:
public interface UserPhotoUploadStrategy {


	String userPhotoUploadToOSS(HttpServletRequest request, HttpServletResponse response,
								MultipartFile file) throws IOException;

}


实现类：

	/**
	 *
	 * @param request 请求信息
	 * @param response 响应信息
	 * @param file 文件输入流
	 * @return key 存在于OSS 的键值
	 * @throws IOException IO流异常
	 */
	@Override
	public String userPhotoUploadToOSS(HttpServletRequest request, HttpServletResponse response,
									   MultipartFile file) throws IOException {

		applicationContext.getBean("oSSUtilsByALiYun");

		String key = "";
		String result ="";

				// 获取上传前源文件名、文件大小
		String originalFileName = file.getOriginalFilename();
		Long originalFileSize  = file.getSize();
		logger.info("上传前的文件名：" + originalFileName);

		// 将 multipartfilein 转化为 inputstream流
		CommonsMultipartFile cFile = (CommonsMultipartFile) file;
		DiskFileItem fileItem = (DiskFileItem) cFile.getFileItem();
		InputStream inputStream = fileItem.getInputStream();

		if (!file.isEmpty()){
			OSSClient ossClient = task07.util.aliyun.oss.OSSUtilsByALiYun.getOSSClient();
			String newFileName = null;
			if (originalFileName.length()>0){
				newFileName = UUID.randomUUID() +"";
			}
			// 将文件上传并获得返回值 key(文件名称)
			key = OSSUtilsByALiYun.uploadObject2OSS(ossClient, inputStream,
					OSSUtilsByALiYun.getBucketName(), originalFileName,newFileName,
					originalFileSize,OSSUtilsByALiYun.getFolder());

		}
		//将文件名写入数据库
		if (!key.equals("")){
			HttpSession userNamesession =request.getSession();
			String userName = (String) userNamesession.getAttribute("userName");

			if (userName.equals(null)){
				logger.info("写入数据库出错，用户名为 null");

			}

			logger.info("userName:" + userName );
			logger.info("key:" + key );

			System.out.println(userLoginDao);
			System.out.println(userLoginDao.queryByName(userName).toString());
			userLoginDao.updateHeadPhoto(userName,key);

			UserLogin userLoginText = userLoginDao.queryByName(userName);
			String databaseHeadPho =  userLoginText.getHead_photo();
			logger.info("写入数据库的key 值为： " + databaseHeadPho);
			// 将 key 值写入数据库


			if (databaseHeadPho.equals(key)){
				logger.info("写入文件一致，上传成功！");
				result = "文件上传成功!";
			}else{
				result = "上传成功，写入数据库不一致!";
			}


		}else {
			logger.info("文件上传失败！");
			result = "文件上传失败!";
		}

		return result;
	}
}
 
策略模式的context :
public class UserPhotoUploadStrategyContext {


	private UserPhotoUploadStrategy userPhotoUploadStrategy;


	public UserPhotoUploadStrategyContext( UserPhotoUploadStrategy userPhotoUploadStrategy){
		this.userPhotoUploadStrategy = userPhotoUploadStrategy;
	}

	public String executeUserPhotoUploadStrategy(HttpServletRequest request, HttpServletResponse response,
												 MultipartFile file) throws IOException {
		System.out.println("context 之前");

		return userPhotoUploadStrategy.userPhotoUploadToOSS(request, response, file);
	}

}

编辑于2024-05-13

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[无名弟子]黄*彬
0

策略模式当成一个工具类来使用，不要嵌套在三层架构中。

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编辑于2018-09-21

去第页