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POentity is null.Why?
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copied!<p>I want to read a JSON of a URL. I searched and test and now i think, i use asynTask because before i don't use asynTask, log writes android.os.NetworkOnMainThreadException. I write this program but i think entity is null becuase log.i in if(entity!=null) not write! I don't know why!</p> <p>GetJSONFromUrl.java</p> <pre><code> @SuppressLint("NewApi") class GetJSONFromUrl extends AsyncTask<String, Void, Void> { InputStream is = null; String result = ""; String error_text=""; JSONObject j = null; @Override protected Void doInBackground(String... urls) { try{ // Create a new HttpClient and Post Header DefaultHttpClient httpclient = new DefaultHttpClient(); HttpGet httpGet = new HttpGet(urls[0]); String resultString = null; Log.i("in function", "getJSONFrom"); long t = System.currentTimeMillis(); HttpResponse response = (HttpResponse) httpclient.execute(httpGet); System.out.println("HTTPResponse received in [" + (System.currentTimeMillis()-t) + "ms]"); // Get hold of the response entity (-> the data): HttpEntity entity = response.getEntity(); if (entity != null) { // Read the content stream InputStream instream = entity.getContent(); // convert content stream to a String resultString= convertStreamToString(instream); instream.close(); System.out.println("result String : " + resultString); Log.i("resultString: ", resultString); //resultString = resultString.substring(1,resultString.length()-1); // remove wrapping "[" and "]" System.out.println("result String : " + resultString); // Transform the String into a JSONObject JSONObject jsonObjRecv = new JSONObject(resultString); // Raw DEBUG output of our received JSON object: System.out.println("<JSONObject>\n"+jsonObjRecv.toString()+"\n</JSONObject>"); Log.i("jsonObjRecv: ", jsonObjRecv.toString()); } }catch(Exception e){e.printStackTrace();} return null; } protected void onPostExecute(String result) { 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(); result = sb.toString(); //System.out.println("Result = " + result); } catch (Exception e) { Log.e("log_tag", "Error converting result " + e.toString()); } } private static String convertStreamToString(InputStream is) { BufferedReader reader = new BufferedReader(new InputStreamReader(is)); StringBuilder sb = new StringBuilder(); String line =""; try { while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } } catch (IOException e) { e.printStackTrace(); } finally { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } return sb.toString(); } } </code></pre> <p>MainActivity.java</p> <pre><code>public class MainActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Log.i("testjson", "test"); new GetJSONFromUrl().execute("http://loyaltier.com/app/mobile/code/places/Maps.php"); } } </code></pre> <p>I see this in logCat:</p> <pre><code> 11-21 11:11:08.446: I/testjson(4756): test 11-21 11:11:08.446: I/in function(4756): getJSONFrom 11-21 11:11:08.454: W/System.err(4756): java.net.UnknownHostException: Unable to resolve host "loyaltier.com": No address associated with hostname 11-21 11:11:08.454: I/WindowManager(177): createSurface Window{42a3c470 org.example.testjson/org.example.testjson.MainActivity paused=false}: DRAW NOW PENDING 11-21 11:11:08.461: W/System.err(4756): at java.net.InetAddress.lookupHostByName(InetAddress.java:426) 11-21 11:11:08.461: W/System.err(4756): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242) 11-21 11:11:08.461: W/System.err(4756): at java.net.InetAddress.getAllByName(InetAddress.java:220) 11-21 11:11:08.461: W/System.err(4756): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137) 11-21 11:11:08.461: W/System.err(4756): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 11-21 11:11:08.461: W/System.err(4756): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 11-21 11:11:08.461: W/System.err(4756): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360) 11-21 11:11:08.461: W/System.err(4756): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) 11-21 11:11:08.461: W/System.err(4756): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 11-21 11:11:08.461: W/System.err(4756): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465) 11-21 11:11:08.461: W/System.err(4756): at org.example.testjson.GetJSONFromUrl.doInBackground(GetJSONFromUrl.java:48) 11-21 11:11:08.461: W/System.err(4756): at org.example.testjson.GetJSONFromUrl.doInBackground(GetJSONFromUrl.java:1) 11-21 11:11:08.461: W/System.err(4756): at android.os.AsyncTask$2.call(AsyncTask.java:264) 11-21 11:11:08.461: W/System.err(4756): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305) 11-21 11:11:08.461: W/System.err(4756): at java.util.concurrent.FutureTask.run(FutureTask.java:137) 11-21 11:11:08.461: W/System.err(4756): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208) 11-21 11:11:08.461: W/System.err(4756): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076) 11-21 11:11:08.461: W/System.err(4756): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569) 11-21 11:11:08.461: W/System.err(4756): at java.lang.Thread.run(Thread.java:856) 11-21 11:11:08.461: W/System.err(4756): Caused by: libcore.io.GaiException: getaddrinfo failed: EAI_NODATA (No address associated with hostname) 11-21 11:11:08.461: W/System.err(4756): at libcore.io.Posix.getaddrinfo(Native Method) 11-21 11:11:08.461: W/System.err(4756): at libcore.io.ForwardingOs.getaddrinfo(ForwardingOs.java:55) 11-21 11:11:08.461: W/System.err(4756): at java.net.InetAddress.lookupHostByName(InetAddress.java:411) 11-21 11:11:08.461: W/System.err(4756): ... 18 more </code></pre> <p>I run the program in my phone. Thanks . Cheers</p>

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