标签:encoder url java NPU 不能 merger color file path
一:将网络文件转为Base64
将文件转为base64
public static String fileToBase64(String url){ int byteread = 0; String total = null; byte[] totalbyte = new byte[0]; try { URL url = new URL(url); URLConnection conn = url.openConnection(); InputStream inStream = conn.getInputStream(); byte[] buffer = new byte[1204]; while ((byteread = inStream.read(buffer)) != -1) { //拼接流,这样写是保证文件不会被篡改 totalbyte = byteMerger(totalbyte,buffer,byteread); } inStream.close(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return Base64.encodeBase64String(totalbyte) }
将base转为文件
public static void base64ToFile(String base64, String filePath) { try { byte[] bytes = Base64.decodeBase64(base64); //base解密 File videoFile = new File(filePath); //输入文件 FileOutputStream fos = new FileOutputStream(videoFile); fos.write(bytes, 0, bytes.length); fos.flush(); fos.close(); } catch (IOException e) { } }
二:将本地文件转Base64
转Base64
public static String videoToBase64(File videofilePath) { long size = videofilePath.length(); byte[] imageByte = new byte[(int) size]; FileInputStream fs = null; BufferedInputStream bis = null; try { fs = new FileInputStream(videofilePath); bis = new BufferedInputStream(fs); bis.read(imageByte); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { if (bis != null) { try { bis.close(); } catch (IOException e) { e.printStackTrace(); } } if (fs != null) { try { fs.close(); } catch (IOException e) { e.printStackTrace(); } } } return Base64.encodeBase64String(imageByte); }
将Base64转文件
public static void base64ToFile(String base64, String filePath) { try { byte[] bytes = Base64.decodeBase64(base64); //base解密 File videoFile = new File(filePath); //输入文件 FileOutputStream fos = new FileOutputStream(videoFile); fos.write(bytes, 0, bytes.length); fos.flush(); fos.close(); } catch (IOException e) { } }
注意:
在将文件转Base64字符时,如果使用sun下的BASE64Encoder时会导致转换出来的Base64自动换行,原因是RFC2045中有规定Base64一行不能超过76字符,超过则添加回车换行符所以导致转换出来的Base64字符会出现换行,解决方法是使用Apache的 commons-codec.jar,Base64.encodeBase64String(byte[])得到的Base64字符不会出现换行
commons-codec 1.4版本时也会出现换行,使用1.8时不会出现换行,其他版本没有测试
<dependency> <groupId>commons-codec</groupId> <artifactId>commons-codec</artifactId> <version>1.8</version> </dependency>
标签:encoder url java NPU 不能 merger color file path
原文地址:https://www.cnblogs.com/wangjinyu/p/12858358.html