Java HTTP请求偶尔会挂起

Question

在大多数情况下,我的HTTP请求工作没有问题.但是,他们偶尔会挂起来.

我正在使用的代码设置为如果请求成功(响应代码为200或201),则调用screen.requestSucceeded().如果请求失败,则调用screen.requestFailed().

但是,当请求挂起时,它会在调用上述方法之一之前执行此操作.我的代码有问题吗？我应该使用某种最佳做法来防止任何悬挂吗？

以下是我的代码.我将不胜感激任何帮助.谢谢!

HttpConnection connection = (HttpConnection) Connector.open(url
                    + connectionParameters);

            connection.setRequestMethod(method);
            connection.setRequestProperty("WWW-Authenticate",
                    "OAuth realm=api.netflix.com");
            if (method.equals("POST") && postData != null) {
            connection.setRequestProperty("Content-Type",
                    "application/x-www-form-urlencoded");
            connection.setRequestProperty("Content-Length", Integer
                    .toString(postData.length));
            OutputStream requestOutput = connection.openOutputStream();
            requestOutput.write(postData);
            requestOutput.close();
        }
            int responseCode = connection.getResponseCode();
            System.out.println("RESPONSE CODE: " + responseCode);
            if (connection instanceof HttpsConnection) {
                HttpsConnection secureConnection = (HttpsConnection) connection;
                String issuer = secureConnection.getSecurityInfo()
                        .getServerCertificate().getIssuer();
                UiApplication.getUiApplication().invokeLater(
                        new DialogRunner(
                                "Secure Connection! Certificate issued by: "
                                        + issuer));

            }

            if (responseCode != 200 && responseCode != 201) {
                screen.requestFailed("Unexpected response code: "
                        + responseCode);
                connection.close();
                return;
            }

            String contentType = connection.getHeaderField("Content-type");
            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            InputStream responseData = connection.openInputStream();
            byte[] buffer = new byte[20000];
            int bytesRead = 0;
            while ((bytesRead = responseData.read(buffer)) > 0) {
                baos.write(buffer, 0, bytesRead);
            }
            baos.close();
            connection.close();
            screen.requestSucceeded(baos.toByteArray(), contentType);
        } catch (IOException ex) {
            screen.requestFailed(ex.toString());
        }

Answer 1

没有任何痕迹,我只是在黑暗中拍摄.

尝试添加这两个电话,

System.setProperty("http.keepAlive", "false");

connection.setRequestProperty("Connection", "close");

保持活跃是陈旧连接的常见原因.这些调用将禁用它.