public class FileUtil {

     //将文件转换成Byte数组

     public static byte[] getBytesByFile(String pathStr) {

         File file = new File(pathStr);

         try {

             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();

             byte[] data = bos.toByteArray();

             bos.close();

             return data;

         } catch (Exception e) {

             e.printStackTrace();

         }

         return null;

     }

     //将Byte数组转换成文件

     public static void getFileByBytes(byte[] bytes, 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(bytes);

         } 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();

                 }

             }

         }

     }

 }