Question

我需要连接到一个Web应用程序，如果请求的URL未在应用程序中映射，则执行HTTP重定向。（例如：/ users - ＆gt; / users /）对于身份验证，我们使用基于令牌的方法，因此我必须为每个请求发送一个令牌。

当我在重定向后设置令牌时，我总是得到java.lang.IllegalStateException: Already connected。有人可以帮我解决这个问题吗？

这是我做的：

try {
      // setup connection
      URL url = new URL(ENDPOINT + path);
      HttpURLConnection connection = (HttpURLConnection) url.openConnection();
      connection.setRequestMethod(method.toString().toUpperCase());
      connection.setInstanceFollowRedirects(false);

      // has the request been redirected?
      if (connection.getResponseCode() == HttpURLConnection.HTTP_MOVED_PERM) {
        String newUrl = connection.getHeaderField("Location");
        connection = (HttpURLConnection) new URL(ENDPOINT + newUrl).openConnection();
      }

      if (useToken) {
        connection.addRequestProperty("Authorization", testToken);
      }

      // post data
      if (data != null) {
        connection.setDoOutput(true);
        connection.addRequestProperty("Content-Type", "application/json");
        String json = new Gson().toJson(data);
        try (OutputStream dataStream = connection.getOutputStream()) {
          dataStream.write(json.getBytes());
        }
      }


      // retrieve response
      String body = IOUtils.toString(connection.getInputStream());
      return new TestResponse(connection.getResponseCode(), body);
    } catch (IOException ex) {
      LOGGER.error(ex.getMessage());
      return null;
    }

Answer 1

我认为你应该设置connection.setInstanceFollowRedirects(true)，这将使连接遵循HTTP重定向然后删除

// has the request been redirected?
      if (connection.getResponseCode() == HttpURLConnection.HTTP_MOVED_PERM) {
        String newUrl = connection.getHeaderField("Location");
        connection = (HttpURLConnection) new URL(ENDPOINT + newUrl).openConnection();

我无法从您的代码中看到为什么需要将setInstanceFollowRedirects设置为false

HttpURLConnection：重定向后已经连接

1 个答案: