1     public static byte[] base64String2ByteFun(String base64Str){  
 2         BASE64Decoder decoder = new BASE64Decoder();
 3         byte[] b = null;
 4         try {
 5             b = decoder.decodeBuffer(base64Str);
 6             for (int i = 0; i < b.length; ++i) {
 7                 if (b[i] < 0) {
 
 8                     b[i] += 256;
 9                 }
10             }
11         } catch (IOException e) {
12             e.printStackTrace();
13         }
14         
15         return b;  
16     }
17     public static String getImageStr(String imgFile) {
18         InputStream inputStream = null
 
;
19         byte[] data = null;
20         try {
21             inputStream = new FileInputStream(imgFile);
22             data = new byte[inputStream.available()];
23             inputStream.read(data);
24             inputStream.close();
25         } catch (IOException e) {
26             e.printStackTrace();
 
27         }
28         BASE64Encoder encoder = new BASE64Encoder();
29         return encoder.encode(data);
30     }

提示：

sun.misc.BASE64Encoder找不到jar包的解決方法

右鍵項目-》屬性-》java bulid path-》jre System Library-》access rules-》resolution選擇accessible，下面填上** 點擊確定即可！！！

java 圖片文件Base64編碼與二進制編碼格式互相轉換