1.网络资源转File
需要引入依赖commons-io /** * 读取网络中的图片 * @param url https://www.kziyue.com/wp-content/uploads/2019/06/5bca-hxyuaph9825616.jpg * @return */ public File URLToFile(String url){ File file1 = new File("test.png"); try { URL url1 = new URL(url); FileUtils.copyURLToFile(url1,file1); } catch (IOException e) { e.printStackTrace(); } File absoluteFile = file1.getAbsoluteFile(); return file1; }
2.网络资源转MultipartFile
需要引入依赖spring-web /** * 文件上传 * @param urlStr url地址 * @return multipartFile */ public MultipartFile fileUpload(String urlStr) throws Exception { try { //把地址转换成URL对象 URL url = new URL(urlStr); //创建http链接 HttpURLConnection conn = (HttpURLConnection)url.openConnection(); //设置超时间为3秒 conn.setConnectTimeout(3*1000); //防止屏蔽程序抓取而返回403错误 conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36)"); //得到输入流 InputStream inputStream = conn.getInputStream(); //截取链接中的文件名 String fileName= urlStr.substring(urlStr.lastIndexOf("/")+1); MultipartFile multipartFile = new MockMultipartFile(fileName,fileName, ContentType.APPLICATION_OCTET_STREAM.toString(), inputStream); return multipartFile; } catch (Exception e) { e.printStackTrace(); } throw new Exception(); }
3.File转MultipartFile
需要引用的依赖spring-text,httpcore /** * 文件类型转换 * * @param filePath 文件file * @return MultipartFile */ public static MultipartFile caseFileToMultipartFile(File filePath) { MultipartFile multipartFile = null; try { log.info("开始进行文件转换"); FileInputStream fileInputStream = new FileInputStream(filePath); multipartFile = new MockMultipartFile(filePath.getName(), filePath.getName(), ContentType.APPLICATION_OCTET_STREAM.toString(), fileInputStream); } catch (IOException e) { e.printStackTrace(); return null; } return multipartFile; }
4.File转字节数组
/** * 将文件转为字节数组 * @param file * @param size 1024 * @return */ public static byte[] BufferStreamForByte(File file, int size) { byte[] content = null; try { BufferedInputStream bis = null; ByteArrayOutputStream out = null; try { FileInputStream input = new FileInputStream(file); bis = new BufferedInputStream(input, size); byte[] bytes = new byte[1024]; int len; out = new ByteArrayOutputStream(); while ((len = bis.read(bytes)) > 0) { out.write(bytes, 0, len); } bis.close(); content = out.toByteArray(); } finally { if (bis != null) { bis.close(); } if (out != null) { out.close(); } } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return content; }
5.Frame转BufferedImage
需要引入依赖javacv public static BufferedImage FrameToBufferedImage(Frame frame) { //创建BufferedImage对象 Java2DFrameConverter converter = new Java2DFrameConverter(); BufferedImage bufferedImage = converter.getBufferedImage(frame); return bufferedImage; }
6.BufferedImage转MultipartFile
public static MultipartFile fileCase(BufferedImage image){ //得到BufferedImage对象 // BufferedImage bufferedImage = JoinTwoImage.testEncode(200, 200, url); MultipartFile multipartFile= null; try { //创建一个ByteArrayOutputStream ByteArrayOutputStream os = new ByteArrayOutputStream(); //把BufferedImage写入ByteArrayOutputStream ImageIO.write(image, "jpg", os); //ByteArrayOutputStream转成InputStream InputStream input = new ByteArrayInputStream(os.toByteArray()); //InputStream转成MultipartFile multipartFile =new MockMultipartFile("file", "file.jpg", "text/plain", input); } catch (IOException e) { e.printStackTrace(); } return multipartFile; }
7. 复制单个文件
/** * 复制单个文件 * @param oldPath String 原文件路径 如:c:/fqf.txt * @param newPath String 复制后路径 如:f:/fqf.txt * @return boolean */ public void copyFile(String oldPath, String newPath) { try { int bytesum = 0; int byteread = 0; File oldfile = new File(oldPath); File fileUploadFile = new File(newPath.substring(newPath.lastIndexOf("\\"))); if (!fileUploadFile.exists()) { fileUploadFile.mkdirs(); } if (oldfile.exists()) { //文件存在时 InputStream inStream = new FileInputStream(oldPath); //读入原文件 FileOutputStream fs = new FileOutputStream(newPath); byte[] buffer = new byte[1444]; int length; while ( (byteread = inStream.read(buffer)) != -1) { bytesum += byteread; //字节数 文件大小 System.out.println(bytesum); fs.write(buffer, 0, byteread); } inStream.close(); } } catch (Exception e) { System.out.println("复制单个文件操作出错"); e.printStackTrace(); } }
标签:multipartFile,return,BufferedImage,地址,File,new,MultipartFile,转换 From: https://www.cnblogs.com/yhc-love-cl/p/16734639.html