HTTP요청 메서드에서 예외처리하기(url, json널값 처리)

주어진 url을 가지고 HTTP요청을 하고 응답을 받는 메서드, makeHttpRequest가 있다.

이 메서드에서

예외처리를 해주어야하는데, 이때 getResponseCode()를 사용해 응답코드가 200이 아닐경우 예외처리 한것을 코드로 살펴보자.

[예외처리 전]

/** * Make an HTTP request to the given URL and return a String as the response. */

private String makeHttpRequest(URL url) throws IOException {
    String jsonResponse = "";

    HttpURLConnection urlConnection = null;

    InputStream inputStream = null;

    try {
        urlConnection = (HttpURLConnection) url.openConnection();

        urlConnection.setRequestMethod("GET");

        urlConnection.setReadTimeout(10000 /* milliseconds */);

        urlConnection.setConnectTimeout(15000 /* milliseconds */);

        urlConnection.connect();

        inputStream = urlConnection.getInputStream();

        jsonResponse = readFromStream(inputStream);

    } catch (IOException e) {
    } finally {
        if (urlConnection != null) {
            urlConnection.disconnect();

        }
        if (inputStream != null) {
            // function must handle java.io.IOException here

            inputStream.close();        }
    }
    return jsonResponse;

[예외처리 후]

private String makeHttpRequest(URL url) throws IOException {
    String jsonResponse = "";


    // if the url is null, we shouldn’t try to make the HTTP request.

    if (url == null){
        return jsonResponse;

    }

    HttpURLConnection urlConnection = null;

    InputStream inputStream = null;

    try {
        urlConnection = (HttpURLConnection) url.openConnection();

        urlConnection.setRequestMethod("GET");

        urlConnection.setReadTimeout(10000 /* milliseconds */);

        urlConnection.setConnectTimeout(15000 /* milliseconds */);

        urlConnection.connect();

       if (urlConnection.getResponseCode() == 200){
           inputStream = urlConnection.getInputStream();

           jsonResponse = readFromStream(inputStream);

    } catch (IOException e) {
    } finally {
        if (urlConnection != null) {
            urlConnection.disconnect();

        }
        if (inputStream != null) {
            // function must handle java.io.IOException here

            inputStream.close();

        }
    }
    return jsonResponse;

예외상황(1,2)에서 리턴값이 초기화값 그대로 출력되는것을 볼 수 있다.

심플.