public static byte[] File2byte(String filePath)    {        byte[] buffer = null;        try        {            File file = new File(filePath);            FileInputStream fis = new FileInputStream(file);            ByteArrayOutputStream bos = new ByteArrayOutputStream();            byte[] b = new byte[1024];            int n;            while ((n = fis.read(b)) != -1)            {                bos.write(b, 0, n);            }            fis.close();            bos.close();            buffer = bos.toByteArray();        }        catch (FileNotFoundException e)        {            e.printStackTrace();        }        catch (IOException e)        {            e.printStackTrace();        }        return buffer;    }    public static void byte2File(byte[] buf, String filePath, String fileName)    {        BufferedOutputStream bos = null;        FileOutputStream fos = null;        File file = null;        try        {            File dir = new File(filePath);            if (!dir.exists() && dir.isDirectory())            {                dir.mkdirs();            }            file = new File(filePath + File.separator + fileName);            fos = new FileOutputStream(file);            bos = new BufferedOutputStream(fos);            bos.write(buf);        }        catch (Exception e)        {            e.printStackTrace();        }        finally        {            if (bos != null)            {                try                {                    bos.close();                }                catch (IOException e)                {                    e.printStackTrace();                }            }            if (fos != null)            {                try                {                    fos.close();                }                catch (IOException e)                {                    e.printStackTrace();                }            }        }    }