byte数组和文件的相互转换

     /**
      * 获得指定文件的byte数组
      */  

     private byte[] getBytes(String filePath){
         byte[] buffer = null;
         try {
             File file = new File(filePath);
             FileInputStream fis = new FileInputStream(file);
             ByteArrayOutputStream bos = new ByteArrayOutputStream(1000);
             byte[] b = new byte[1000];
             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;
     }

     /**
      * 根据byte数组，生成文件
      */
     public static void getFile(byte[] bfile, String filePath,String fileName) {
         BufferedOutputStream bos = null;
         FileOutputStream fos = null;
         File file = null;
         try {
             File dir = new File(filePath);
             if(!dir.exists()&&dir.isDirectory()){//判断文件目录是否存在
                 dir.mkdirs();
             }
             file = new File(filePath+"\\"+fileName);
             fos = new FileOutputStream(file);
             bos = new BufferedOutputStream(fos);
             bos.write(bfile);
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             if (bos != null) {
                 try {
                     bos.close();
                 } catch (IOException e1) {
                     e1.printStackTrace();
                 }
             }
             if (fos != null) {
                 try {
                     fos.close();
                 } catch (IOException e1) {
                     e1.printStackTrace();
                 }
             }
         }
     }