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Asked:2022-02-07 15:41:50 +0000 UTC2022-02-07 15:41:50 +0000 UTC

无法在android中发出http请求

  • 772

我无法在 Android 中发出 http 请求，代码如下；权限在清单中

public class WebRequests {
    public String getContent(String http) throws IOException {
        HttpURLConnection connection = null;
        String line = null;
        try {
            connection = (HttpURLConnection) new URL(http).openConnection();

            connection.setRequestMethod("GET");
            connection.setUseCaches(false);
            connection.setConnectTimeout(250);
            connection.setReadTimeout(250);

            connection.connect();

            StringBuilder sb = new StringBuilder();

            if (HttpURLConnection.HTTP_OK == connection.getResponseCode()) {
                BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));

                while ((line = in.readLine()) != null) {
                    sb.append(line);
                }
                Log.d("WebReqeust", line);
            } else {
                Log.e("WebRequest", connection.getResponseCode() + ", " + connection.getResponseMessage());
            }
        } catch (Throwable cause) {
            cause.printStackTrace();
        } finally {
            if (connection != null) {
                connection.disconnect();
            }
        }
        return line;
    }
}
java

1 个回答

  1. Best Answer

    这是天气查询代码

        public static JSONObject getWeatherJSON(String lat, String lon){
    String _input = "http://api.openweathermap.org/data/2.5/weather?lat=" + lat + "&lon=" + lon;
    URL url = null;
    try {
        url = new URL(_input);
    } catch (MalformedURLException e) {
        e.printStackTrace();
    }
    HttpURLConnection connection = null;
    try {
        connection = (HttpURLConnection)url.openConnection();
    } catch (IOException e) {
        e.printStackTrace();
    }

    BufferedReader reader = null;
    try {
        reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
    } catch (IOException e) {
        e.printStackTrace();
    }

    StringBuilder json = new StringBuilder(1024);
        String tmp="";
        while(true) {
            try {
                if ((tmp = reader.readLine()) == null) break;
            } catch (IOException e) {
                e.printStackTrace();
            }
            json.append(tmp).append("\n");
        }
    try {
        reader.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

    JSONObject data = null;
    try {
        data = new JSONObject(json.toString());
    } catch (JSONException e) {
        e.printStackTrace();
    }

    // This value will be 404 if the request was not
        // successful
    try {
        if (data.getInt("cod") != 200){
            return null;
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }

    return data;
}

    加上清单中的规定

            android:usesCleartextTraffic="true"
    • 1

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