将文件变成字符串，又还原成文件

将文件变成字符串，再还原成文件

byte[] sfile = getBytes("D:\\4.png");Base64 base64 = new Base64();byte[] a=base64.encode(sfile);try {String str = new String(a,"utf-8");System.out.println("字符串长度："+str.length());byte[] xml=str.getBytes("UTF-8");byte[] b=base64.decode(xml);setFile(b, "c:\", "4.png");} catch (UnsupportedEncodingException e) {e.printStackTrace();}