Parse Json to String

Parse Json to String

I want to parse Json to string, to show it on a listView. I search and
read lots of Articles and questions but I can't find the solution
I've tried this parser JSON From: Android JSON Parsing Tutorial
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(String url) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
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();
}
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();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
And another one from How to parse JSON in Android :
DefaultHttpClient httpclient = new DefaultHttpClient(new
BasicHttpParams());
HttpPost httppost = new HttpPost("http://someJSONUrl.com/jsonWebService");
// Depends on your web service
httppost.setHeader("Content-type", "application/json");
InputStream inputStream = null;
String result = null;
try {
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
inputStream = entity.getContent();
// json is UTF-8 by default
BufferedReader reader = new BufferedReader(new
InputStreamReader(inputStream, "UTF-8"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null)
{
sb.append(line + "\n");
}
result = sb.toString();
} catch (Exception e) {
// Oops
}
finally {
try{if(inputStream != null)inputStream.close();}catch(Exception squish){}
}
but in both of them when I use a string Json , everything is ok , but when
I want to Read Json from a Web API (ex:
http://api.androidhive.info/contacts/) this errors comes to me:
09-27 23:47:11.015: E/AndroidRuntime(28635): FATAL EXCEPTION: main 09-27
23:47:11.015: E/AndroidRuntime(28635): java.lang.RuntimeException: Unable
to start activity
ComponentInfo{com.mas.forcheksulotion/com.mas.forcheksulotion.MainActivity}:
java.lang.NullPointerException 09-27 23:47:11.015:
E/AndroidRuntime(28635): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1666)
09-27 23:47:11.015: E/AndroidRuntime(28635): at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1682)
09-27 23:47:11.015: E/AndroidRuntime(28635): at
android.app.ActivityThread.access$1500(ActivityThread.java:117) 09-27
23:47:11.015: E/AndroidRuntime(28635): at
android.app.ActivityThread$H.handleMessage(ActivityThread.java:943) 09-27
23:47:11.015: E/AndroidRuntime(28635): at
android.os.Handler.dispatchMessage(Handler.java:99) 09-27 23:47:11.015:
E/AndroidRuntime(28635): at android.os.Looper.loop(Looper.java:130) 09-27
23:47:11.015: E/AndroidRuntime(28635): at
android.app.ActivityThread.main(ActivityThread.java:3744) 09-27
23:47:11.015: E/AndroidRuntime(28635): at
java.lang.reflect.Method.invokeNative(Native Method) 09-27 23:47:11.015:
E/AndroidRuntime(28635): at
java.lang.reflect.Method.invoke(Method.java:507) 09-27 23:47:11.015:
E/AndroidRuntime(28635): at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
09-27 23:47:11.015: E/AndroidRuntime(28635): at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 09-27
23:47:11.015: E/AndroidRuntime(28635): at
dalvik.system.NativeStart.main(Native Method) 09-27 23:47:11.015:
E/AndroidRuntime(28635): Caused by: java.lang.NullPointerException 09-27
23:47:11.015: E/AndroidRuntime(28635): at
java.io.StringReader.(StringReader.java:46) 09-27 23:47:11.015:
E/AndroidRuntime(28635): at
org.json.simple.JSONValue.parse(JSONValue.java:33) 09-27 23:47:11.015:
E/AndroidRuntime(28635): at
com.mas.forcheksulotion.MainActivity.onCreate(MainActivity.java:57) 09-27
23:47:11.015: E/AndroidRuntime(28635): at
android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
09-27 23:47:11.015: E/AndroidRuntime(28635): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1630)
09-27 23:47:11.015: E/AndroidRuntime(28635): ... 11 more
And still I don't know for using Json on android I should work with
JSONArray , or JSONObject or parse Json to String ?!