public class ImgBase64 {
     public static void main(String[] args) //測試
        {
             
            String strImg = GetImageStr();
            System.out.println(strImg);
        }
        public static String GetImageStr()//圖片轉base64
        {//圖片路徑
            String imgFile = "D:\\Users\\sys\\Pictures\\1.png
 
";//
            InputStream in = null;
            byte[] data = null;
         
            try 
            {
                in = new FileInputStream(imgFile);        
                data = new byte[in.available()];
                in.read(data);
                in.close();
            } 
            
 
catch (IOException e) 
            {
                e.printStackTrace();
            }
           
            BASE64Encoder encoder = new BASE64Encoder();
            return encoder.encode(data);//
        }
        public static boolean GenerateImage(String imgStr)//base字符串轉圖片
        {//
            if
 
 (imgStr == null) //
                return false;
            BASE64Decoder decoder = new BASE64Decoder();
            try 
            {
              
                byte[] b = decoder.decodeBuffer(imgStr);
                for(int i=0;i<b.length;++i)
                {
                    if(b[i]<0) //糾正錯誤字符
                    {
                        b[i]+=256;
                    }
                }
               
                String imgFilePath = "d:\\222.jpg";//
                OutputStream out = new FileOutputStream(imgFilePath);    
                out.write(b);
                out.flush();
                out.close();
                return true;
            } 
            catch (Exception e) 
            {
                return false;
            }
        }
}

java 圖片base64互轉