java中File与byte[]互转

public class FileUtile {
    /**
     * 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(1024);
            byte[] b = new byte[1024];
            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 File getFileByBytes(byte[] bytes, String filePath, String fileName) {
        BufferedOutputStream bos = null;
        FileOutputStream fos = null;
        File file = null;
        try {
            File dir = new File(filePath);
            // 判断文件目录是否存在
            if (!dir.exists()) {
                dir.mkdirs();
            }
            file = new File(filePath + fileName);
            fos = new FileOutputStream(file);
            bos = new BufferedOutputStream(fos);
            bos.write(bytes);
            return file;
        } catch (Exception e) {
            e.printStackTrace();
            return file;
        } finally {
            if (bos != null) {
                try {
                    bos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}