Question

在调试期间，我意识到我设置的所有请求属性和方法都没有执行。任何人都可以解释原因吗？

因此，每当我请求URLConnection的输出时，该行都会产生运行时错误。

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    try {
        url = new URL("https://ussouthcentral.services.azureml.net/workspaces/80b0369fe0df48308d956e2ddce52806/services/6379155db28f4c91b84e78d268a927f9/execute?api-version=2.0&format=swagger");
    } catch (MalformedURLException e) {
        e.printStackTrace();
    }
    try {
        urlConnection = (URLConnection) url.openConnection();
        urlConnection.setDoOutput(true);
       // urlConnection.setRequestMethod("POST");

        String api_key = "Bearer api_key";
        urlConnection.setDoInput(true);

        urlConnection.addRequestProperty("Authorization", api_key);
        urlConnection.addRequestProperty("Content-Type", "application/json");
        urlConnection.addRequestProperty("Accept", "application/json");
         } catch (IOException e) {
        e.printStackTrace();
    }

   try {
        urlConnection.connect();
        urlConnection.getContent();
    } catch (IOException e) {
        e.printStackTrace();
    }

Answer 1

首先，你在UI操作系统不允许的UI线程上进行网络操作，你应该把你的代码放在异步任务中

像这样：

AsyncTask<Void, Void, Void> task = new AsyncTask<Void, Void, Void>() {
        @Override
        protected Void doInBackground(Void... params) {
            URL url = null;
            URLConnection urlConnection = null;
            try {
                url = new URL("https://ussouthcentral.services.azureml.net/workspaces/80b0369fe0df48308d956e2ddce52806/services/6379155db28f4c91b84e78d268a927f9/execute?api-version=2.0&format=swagger");
                urlConnection = (URLConnection) url.openConnection();
                urlConnection.setDoOutput(true);
                // urlConnection.setRequestMethod("POST");

                String api_key = "Bearer api_key";
                urlConnection.setDoInput(true);

                urlConnection.addRequestProperty("Authorization", api_key);
                urlConnection.addRequestProperty("Content-Type", "application/json");
                urlConnection.addRequestProperty("Accept", "application/json");
                urlConnection.connect();
                urlConnection.getContent();
            }
            catch (IOException exc) {
                exc.printStackTrace();
            }
            return null;
        }
    };

    task.execute();

还要确保清单中有intenet权限

<uses-permission android:name="android.permission.INTERNET" />

也是你的api密钥＆＃34; Bearer api_key＆＃34;不是有效的API密钥

Answer 2

在Activity.onCreate中发送网络请求会导致您的应用程序崩溃NetworkOnMainThreadException，您永远不应该这样做
我强烈建议您使用其他网络库来处理您在此处遇到的大部分问题，例如OkHttp，Volley或Retrofit

Answer 3

尝试以下发送帖子请求

try {
    url = new URL("https://ussouthcentral.services.azureml.net/workspaces/80b0369fe0df48308d956e2ddce52806/services/6379155db28f4c91b84e78d268a927f9/execute");

} catch (MalformedURLException e) {
    e.printStackTrace();
}
try {
    String requestBody = "api-version=2.0&format=swagger"
    urlConnection = (URLConnection) url.openConnection();
    String api_key = "Bearer api_key";

    urlConnection.addRequestProperty("Authorization", api_key);
    urlConnection.addRequestProperty("Content-Type", "application/json");
    urlConnection.addRequestProperty("Accept", "application/json");
    urlConnection.setDoOutput(true);
    OutputStreamWriter writer = new OutputStreamWriter(urlConnection.getOutputStream(),"UTF-8");
    writer.write(requestBody);
    writer.flush();
    if (urlconnection.getResponseCode() == 200) 
     {                  
            InputStream input = urlconnection.getInputStream();
            //parse the response
     }

  } catch (IOException e) {
    e.printStackTrace();
}

POST方法未设置

3 个答案: