Android httpURLConnection

[Martial Britto]

The Code below on execution in android throws IOException but not when executed as a java project.

public String convert(String from, String to,int amt){
    String result= null;
    URL url = null;
    HttpURLConnection urlConnection = null;
    try {
        url = new URL("http://www.exchangerate-api.com/"+from+"/"+to+"/"+amt+"?k=......");
        System.out.println("hai");
        urlConnection = (HttpURLConnection) url.openConnection();
        InputStream in = new BufferedInputStream(urlConnection.getInputStream());
        result = readStream(in);
        System.out.println(result);
    } catch (MalformedURLException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return result;
}
public static String readStream(InputStream in) throws IOException {
    StringBuilder sb = new StringBuilder();
    BufferedReader r = new BufferedReader(new InputStreamReader(in),1000);
    for (String line = r.readLine(); line != null; line =r.readLine()){
        sb.append(line);
    }
    in.close();
    return sb.toString();
} 

This piece of code works fine when executed as a java project but not as an android project.. kindly reply soon

[zoheb hassan]

Can you post the manifest, Have you added this node <uses-permission android:name="android.permission.INTERNET" /> in your manifest

[lillinonahfirstname lillinonahlastname]

as @zoheb has corrected pointed out, missing <uses-permission android:name="android.permission.INTERNET" /> sounds like the culprit and is common

that said for others coming across this issue who have already added the INTERNET permission, another thing to check is to see if you are getting the NetworkOnMainThreadException

in @Martial's code snippet only MalforedURLException and IOException are being caught therefore would miss the NetworkOnMainThreadException if this snippet happened to be on the main thread (not suggesting it is in @Martial's case)

the idea is to safeguard the responsiveness of the main thread by disallowing network, for more info see here:

http://developer.android.com/reference/android/os/NetworkOnMainThreadException.html

[Peter Johnson]

"lillinonahfirstname lillinonahlastname", please see your private messages regarding an important administrative matter.