Trying to get xml from url but getting FATAL ERROR: main

Question

Iam a beginner programing in android and java so excuse me if the code is wrong. I'm just trying to get some xml from a url and then display it in logcat but i keep getting the same errors.

Here is the log:

01-01 19:49:38.065: E/Trace(6471): error opening trace file: No such file or directory (2)
01-01 19:49:38.225: D/AndroidRuntime(6471): Shutting down VM
01-01 19:49:38.225: W/dalvikvm(6471): threadid=1: thread exiting with uncaught exception (group=0x40c72300)
01-01 19:49:38.795: E/AndroidRuntime(6471): FATAL EXCEPTION: main
01-01 19:49:38.795: E/AndroidRuntime(6471): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.alexisdelatorre.helloxml/com.alexisdelatorre.helloxml.MainActivity}: android.os.NetworkOnMainThreadException
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.ActivityThread.access$600(ActivityThread.java:130)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.os.Handler.dispatchMessage(Handler.java:99)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.os.Looper.loop(Looper.java:137)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.ActivityThread.main(ActivityThread.java:4745)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at java.lang.reflect.Method.invokeNative(Native Method)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at java.lang.reflect.Method.invoke(Method.java:511)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at dalvik.system.NativeStart.main(Native Method)
01-01 19:49:38.795: E/AndroidRuntime(6471): Caused by: android.os.NetworkOnMainThreadException
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at java.net.InetAddress.getAllByName(InetAddress.java:214)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at com.alexisdelatorre.helloxml.JavaXmlTutorial.getXmlFromUrl(JavaXmlTutorial.java:64)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at com.alexisdelatorre.helloxml.JavaXmlTutorial.<init>(JavaXmlTutorial.java:31)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at com.alexisdelatorre.helloxml.MainActivity.onCreate(MainActivity.java:21)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.Activity.performCreate(Activity.java:5008)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
01-01 19:49:38.795: E/AndroidRuntime(6471):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
01-01 19:49:38.795: E/AndroidRuntime(6471):     ... 11 more

And the code:

package com.alexisdelatorre.helloxml;

import java.io.IOException;

public class JavaXmlTutorial {

    public JavaXmlTutorial() throws XmlPullParserException, IOException{


        String xmlFromUrl = getXmlFromUrl("http://api.androidhive.info/pizza/?format=xml");

        XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
        factory.setNamespaceAware(true);
        XmlPullParser xpp = factory.newPullParser();

        xpp.setInput(new StringReader (xmlFromUrl));
        int eventType = xpp.getEventType();
        while (eventType != XmlPullParser.END_DOCUMENT) {
         if(eventType == XmlPullParser.START_DOCUMENT) {
             Log.d(TAGS.DEBUG, "start document");
         } else if(eventType == XmlPullParser.END_DOCUMENT) {
             Log.d(TAGS.DEBUG, "end document");
         } else if(eventType == XmlPullParser.START_TAG) {
             Log.d(TAGS.DEBUG,"Start tag "+xpp.getName());
         } else if(eventType == XmlPullParser.END_TAG) {
             Log.d(TAGS.DEBUG,"End tag "+xpp.getName());
         } else if(eventType == XmlPullParser.TEXT) {
             Log.d(TAGS.DEBUG,"Text "+xpp.getText());
         }
         eventType = xpp.next();
        }

    }

    public String getXmlFromUrl(String url) {
        String xml = null;

        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            xml = EntityUtils.toString(httpEntity);

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        // return XML
        return xml;
    }


}

Try to run your `JavaXmlTutorial` in `AsyncTask`. – GrIsHu Jan 01 '14 at 04:41 — GrIsHu, Jan 01 '14 at 04:41

GrIsHu · Accepted Answer · 2014-01-01T04:57:23.193

0

You can't make HTTP requests on the main thread, it would cause the UI to freeze up. So it throws NetworkOnMainThreadException exception. You need to do it in an AsyncTask or another Thread.

Check out NetworkOnMainThreadException

class SynchTask extends AsyncTask<Void,Void,Void>
{
          protected void onPreExecute()
          {           super.onPreExecute();
                    //display progressdialog.
          } 

           protected void doInBackground(Void ...params)
          {  
                //http request. do not update ui here
                  JavaXmlTutorial parse=new JavaXmlTutorial();
                 return null;
          } 
          protected void onPostExecute(Void result)
          {     
                    super.onPostExecute(result);
                    //dismiss progressdialog.
                    //update ui
          } 
}

edited Jan 01 '14 at 04:57

answered Jan 01 '14 at 04:43

GrIsHu

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Sorry for the ignorance but, can you give me an example? or an url? – Alxs24 Jan 01 '14 at 04:46
oh, i think that i have to do some research if i want to mess with xml. well, thank you, you realy helped me a lot. – Alxs24 Jan 01 '14 at 05:05
You're Welcome. :) Happy New Year :) @Alxs24 – GrIsHu Jan 01 '14 at 05:06
@Alxs24 to be clear, this has *nothing* to do with xml – Brian Roach Jan 01 '14 at 05:06
xD thank you, and happy new year to everyone – Alxs24 Jan 01 '14 at 05:08

Trying to get xml from url but getting FATAL ERROR: main

1 Answers1