Spring MVC實現文件上傳和下載

本文實例為大家分享了Spring MVC實現文件上傳和下載的具體代碼，供大家參考，具體內容如下

1、導入主要依賴

<!--文件上傳--><dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.3</version></dependency><!--servlet-api導入高版本的--><dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>4.0.1</version></dependency>

2、配置bean：multipartResolver（注：此bena的id必須為：multipartResolver ， 否則上傳文件會報400的錯誤?。?/p>

<!--文件上傳配置--><bean class='org.springframework.web.multipart.commons.CommonsMultipartResolver'> <!-- 請求的編碼格式，必須和jSP的pageEncoding屬性一致，以便正確讀取表單的內容， 默認為ISO-8859-1 --> <property name='defaultEncoding' value='utf-8'/> <!-- 上傳文件大小上限，單位為字節（10485760=10M） --> <property name='maxUploadSize' value='10485760'/> <property name='maxInMemorySize' value='40960'/></bean>

3、index.jsp

4、Controller

@RestControllerpublic class FileController { //@RequestParam('file') 將name=file控件得到的文件封裝成 CommonsMultipartFile 對象 //批量上傳 CommonsMultipartFile 則為數組即可 @RequestMapping('/upload') public String fileUpload(@RequestParam('file') CommonsMultipartFile file, HttpServletRequest request) throws IOException {//獲取文件名 : file.getOriginalFilename();String uploadFileName = file.getOriginalFilename();//如果文件名為空，直接回到首頁！if (''.equals(uploadFileName)) { return 'redirect:/index.jsp';}System.out.println('上傳文件名 : ' + uploadFileName);//上傳路徑保存設置String path = request.getServletContext().getRealPath('/upload');//如果路徑不存在，創建一個File realPath = new File(path);if (!realPath.exists()) { realPath.mkdir();}System.out.println('上傳文件保存地址：' + realPath);InputStream is = file.getInputStream(); //文件輸入流OutputStream os = new FileOutputStream(new File(realPath, uploadFileName)); //文件輸出流//讀取寫出int len = 0;byte[] buffer = new byte[1024];while ((len = is.read(buffer)) != -1) { os.write(buffer, 0, len); os.flush();}os.close();is.close();return 'redirect:/index.jsp'; } /* * 采用file.Transto 來保存上傳的文件 */ @RequestMapping('/upload2') public String fileUpload2(@RequestParam('file') CommonsMultipartFile file, HttpServletRequest request) throws IOException {//上傳路徑保存設置String path = request.getServletContext().getRealPath('/upload');File realPath = new File(path);if (!realPath.exists()) { realPath.mkdir();}System.out.println('上傳文件保存地址：' + realPath);//通過CommonsMultipartFile的方法直接寫文件（注意這個時候）file.transferTo(new File(realPath + '/' + file.getOriginalFilename()));return 'redirect:/index.jsp'; }}

index.jsp

Controller

@RequestMapping(value = '/download')public String downloads(HttpServletResponse response, HttpServletRequest request) throws Exception { //要下載的圖片地址 String path = request.getServletContext().getRealPath('/upload'); String fileName = '基礎語法.jpg'; //1、設置response 響應頭 response.reset(); //設置頁面不緩存,清空buffer response.setCharacterEncoding('UTF-8'); //字符編碼 response.setContentType('multipart/form-data'); //二進制傳輸數據 //設置響應頭 response.setHeader('Content-Disposition', 'attachment;fileName=' + URLEncoder.encode(fileName, 'UTF-8')); File file = new File(path, fileName); //2、 讀取文件--輸入流 InputStream input = new FileInputStream(file); //3、 寫出文件--輸出流 OutputStream out = response.getOutputStream(); byte[] buff = new byte[1024]; int index = 0; //4、執行 寫出操作 while ((index = input.read(buff)) != -1) {out.write(buff, 0, index);out.flush(); } out.close(); input.close(); return null;}

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持好吧啦網。