java文件和字節數組之間的轉換

 public static void main(String[] args) throws IOException {
        File file = new File(
                "C:\\Users\\Administrator\\Documents\\WeChat Files\\x564236578\\FileStorage\\File\\2019-07\\123.sql");
        byte[] aa = InputStream2ByteArray("C:\\Users\\Administrator\\Documents\\WeChat Files\\x564236578\\FileStorage\\File\\2019-07\\123.sql");
                System.out.println(aa);
        System.out.println("-------------");
        String json = JSON.toJSONString(aa);
        byte[] bb = JSON.parseObject(json,byte[].class);
        getFileByBytes(bb,"H:\\","111.sql");
        System.out.println("bb====="+bb);
        System.out.println(json);
    }
    private static byte[] InputStream2ByteArray(String filePath) throws IOException {

        InputStream in = new FileInputStream(filePath);
        byte[] data = toByteArray(in);
        in.close();

        return data;
    }

    private static byte[] toByteArray(InputStream in) throws IOException {

        ByteArrayOutputStream out = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024 * 4];
        int n = 0;
        while ((n = in.read(buffer)) != -1) {
            out.write(buffer, 0, n);
        }
        return out.toByteArray();
    }

    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()) {// 判斷文件目錄是否存在
                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();
                }
            }
        }
    }