Android Studio 1.5.1中的JSON解析

我在 Eclipse ADT 上进行了 JSON 解析，并且运行完美。但是，当在 Android Studio 上使用相同的代码时，它在 DefaultHttpClient 和该块中的所有其他单词中显示错误。

这是我的 JSON 解析器类

JSONParser.java

public class JSONParser {

    JSONArray cArray;
    JSONObject jsonObj;
    InputStream is = null;
    String jsonStr = "";
    String urlString;
    Context context;
    String id;
    String name, email, mobile;

    Contacts contacts;
    List < Contacts > contactList;

    public JSONParser() {
        // TODO Auto-generated constructor stub
    }

    public JSONParser(String url) {
        this.urlString = url;
    }

    public List < Contacts > getString() {

        contactList = new ArrayList < Contacts > ();

        try {
            // **Error in this block**

            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(urlString);

            HttpResponse httpResponse = httpClient.execute(httpPost);

            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (NullPointerException e) {
            Log.e("NULL DATA", "cant fetch " + e.toString());
        }

        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
            StringBuilder sb = new StringBuilder();

            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
            is.close();
            jsonStr = sb.toString();


        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }


        if (jsonStr != null) {
            try {

                cArray = new JSONArray(jsonStr);

                JSONObject jsonObj = null;

                // looping through All Contacts
                for (int i = 0; i < cArray.length(); i++) {
                    jsonObj = cArray.getJSONObject(i);

                    id = jsonObj.getString("foodno");
                    name = jsonObj.getString("foodname");
                    email = jsonObj.getString("foodtype");

                    /* JSONObject phoneNo = jsonObj.getJSONObject("phone");
                     mobile = phoneNo.getString("mobile");*/

                    contacts = new Contacts(id, name, email);


                    // adding contact to contact list
                    contactList.add(contacts);
                }
            } catch (JSONException e) {
                e.printStackTrace();
            } catch (NullPointerException e) {
                e.printStackTrace();
            }

        } else {
            Log.e("JSONParser", "Couldn't get any data from the url");
        }


        return contactList;

    }

}

谁能建议如何连接以获取可以传递给 BufferedReader 的 json 字符串？

我强烈建议您使用图书馆来完成这项工作。你可以使用GSON lib https://github.com/google/gson（由谷歌开发）或杰克逊·利布 https://github.com/FasterXML/jackson。对于您可以使用的请求改造库 http://square.github.io/retrofit/（由 Square 开发）。