Java将字节数组转换为PDF返回“undefined”

Question

我正在尝试将字节数组转换为PDF文档，但PDF文件似乎已损坏。如果用文本阅读器打开文件，文件只是说“未定义”我搜索了各种堆栈主题但没有运气。我这样做的方式应该按照其他主题进行。以下是我的代码。代码通过休息控制器执行。如果有人可以帮助我，我真的很感激:)。

//控制器

@ResponseBody
  @RequestMapping(value = "/orders/{orderCode}/receipt", method = RequestMethod.GET, produces = "application/pdf")
  public void getOrderReceiptConroller(@PathVariable("orderCode") final String orderCode, final HttpServletResponse response)
  {
    response.setContentType(CoreConstants.MIME_TYPE_APPLICATION_PDF);
    final InputStream inputStream = new ByteArrayInputStream(OrderFacade.getReceiptPdf(orderCode));
    OutputStream outputStream = null;
    try
    {
      outputStream = response.getOutputStream();
      IOUtils.copy(inputStream, outputStream);
    }
    catch (final IOException e)
    {

    }
    finally
    {
      IOUtils.closeQuietly(inputStream);
      IOUtils.closeQuietly(outputStream);
    }
  }


// calls this code that returns the byteArray.
private byte[] getReceiptPdf()
    {
            Gson gson = new Gson();
            Edwresults edwResult = gson.fromJson(new FileReader(mockResponsePath), Edwresults.class);
            String response = edwResult.getResults().get(0).getData().get(0).getDigitalReceipt();
            byte[] byteData = response.getBytes();
            return byteData;
    }