1.网络资源转File
需要引入依赖commons-io
|
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/** * 读取网络中的图片 * @param url https://HdhCmsTestkziyue测试数据/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
|
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/** * 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
|
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/** * 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
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/** * 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
|
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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
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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;
} |
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原文链接：https://blog.csdn.net/promsing/article/details/123269347
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