首页 > 代码库 > Java文件上传下载

Java文件上传下载

Java文件上传下载

 

相关 jar 包:

commons-beanutils.jar

commons-collections.jar

commons-fileupload-1.2.2.jar

commons-io-2.4.jar

commons-lang.jar

commons-logging.jar

dom4j-1.6.1.jar

ezmorph-1.0.6.jar

 

jar 包下载:http://files.cnblogs.com/files/liaolongjun/common-jar.zip

 

    void upload() throws Exception {		for (FileItem item : FileUtil.getFileItems(request)) {			ServletContext sc = request.getServletContext();			String path = sc.getRealPath("upload"); // 上传的文件存储路劲			String filename = item.getName();			File file = new File(path + File.separator + filename);			System.out.println(file);			if (file.exists() || file.createNewFile()) {				item.write(file); // 保存文件			}			// 输出 Base64 - item.get() 获取 byte[]			System.out.println("data:" + item.getContentType() + ";base64," + new String(Base64.encodeBase64(item.get())));		}	}	void download() throws Exception {		String filepath = request.getParameter("filepath");		File file = new File(filepath);		response.reset();		response.setContentType("application/x-msdownload");		response.addHeader("Content-Disposition", "attachment; filename=\"" + URLEncoder.encode(file.getName(), "utf-8") + "\"");		int fileLength = (int) file.length();		response.setContentLength(fileLength);		FileUtil.i2o(new BufferedInputStream(new FileInputStream(file)), response.getOutputStream());	}

 

FileUtil.getFileItems 方法:

	/**	 * DiskFileItemFactory 为解析器提供解析时的缺省的配置 <br>	 * ServletFileUpload 解析 InputStream,将一个表单域(比如,一个文件输入框)中的数据封装到一个FileItem对象上<br>	 * FileItem对象上提供了相应的方法来获取表单域中的数据	 */	public static List<FileItem> getFileItems(HttpServletRequest request) {		List<FileItem> fileItems = new ArrayList<>();		try {			ServletFileUpload sfu = new ServletFileUpload(new DiskFileItemFactory());			for (Object obj : sfu.parseRequest(request)) {				FileItem item = (FileItem) obj;				if (!item.isFormField()) { // 是否普通表单域					fileItems.add(item);				}			}		} catch (Exception e) {			throw new RuntimeException(e);		}		return fileItems;	}

  

FileUtil.i2o 方法:

	public static void i2o(InputStream is, OutputStream os) {		try {			byte[] b = new byte[1024 * 1024]; // 一次读取1M			int n = 0;			while ((n = is.read(b)) != -1)				os.write(b, 0, n);// 这个n还不能去了			is.close();			os.flush();			os.close();		} catch (IOException e) {			e.printStackTrace();		}	}

  

Java文件上传下载