问使用GSON Android解析json时出现空指针异常

EN

{"eventId":"1","eventTitle":"opening ceremony","eventCategory":"store","eventSubCategory":"clothing","eventDescription":"This is an event description of some kid for the first event","eventDate":"13/05/2012","eventTime":"14:52","eventAddress":"49 somerset road","eventCity":"southsea","eventCountry":"UK","eventWebsite":"www.nxtldn.com","eventEmail":"lg@nxtldn.com","eventPhone":"07757491567","eventKeywords":"clothes, street, wear, heart, love"},{"eventId":"2","eventTitle":"cupcakes","eventCategory":"Store","eventSubCategory":"food","eventDescription":"This is an event description of some kid for the second event","eventDate":"17/05/2012","eventTime":"11:22","eventAddress":"12 cleveleys road","eventCity":"london","eventCountry":"UK","eventWebsite":"www.ashshort.com","eventEmail":"ashshort@short.com","eventPhone":"0778514562","eventKeywords":"cupcakes, store, london, hipster"}]

{"Events":[{"eventId":"1","eventTitle":"opening ceremony","eventCategory":"store","eventSubCategory":"clothing","eventDescription":"This is an event description of some kid for the first event","eventDate":"13/05/2012","eventTime":"14:52","eventAddress":"49 somerset road","eventCity":"southsea","eventCountry":"UK","eventWebsite":"www.nxtldn.com","eventEmail":"lg@nxtldn.com","eventPhone":"07757491567","eventKeywords":"clothes, street, wear, heart, love"},{"eventId":"2","eventTitle":"cupcakes","eventCategory":"Store","eventSubCategory":"food","eventDescription":"This is an event description of some kid for the second event","eventDate":"17/05/2012","eventTime":"11:22","eventAddress":"12 cleveleys road","eventCity":"london","eventCountry":"UK","eventWebsite":"www.ashshort.com","eventEmail":"ashshort@short.com","eventPhone":"0778514562","eventKeywords":"cupcakes, store, london, hipster"}]}

public class EventSync extends AsyncTask<String, Integer, EventsList> {

EventsList elist1 = new EventsList();

@Override
protected EventsList doInBackground(String... urls) {
    String tempurl = urls[0];
    String output = "";
    InputStream is = null;
    StringBuilder sb = new StringBuilder();
    EventsList list = new EventsList();
    try
    {
        URL url = new URL(tempurl);
        HttpURLConnection con = (HttpURLConnection) url.openConnection();
        con.connect();
        is = con.getInputStream();

        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
        String line = null;

        while((line = reader.readLine()) != null)
        {
            sb.append(line + "\n");
        }

    }
    catch (Exception e)
    {
        e.printStackTrace();
    }
    finally
    {
        try
        {
            is.close();
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
    }

    output = sb.toString();
    String json = "{\"Events\":" + output + "}";
    System.out.println(json);
    Gson gson = new Gson();
// When debugging this is the line I believe it fails on, It points to a bit of memory but the list is empty.
    EventsList jsonlist = gson.fromJson(json, EventsList.class);

    return jsonlist;
}

@Override 
protected void onPostExecute(EventsList list)
{

    System.out.println("in on post");
    for (Event event : list.getEvents())
    {
        System.out.println(event.getEventId());
    }
}}

public class EventsList {

public EventsList(){

}

private List<Event> events;

public List<Event> getEvents()
{
    return events;
}

public void setEventsList(List<Event> events)
{
    this.events = events;
}}

public class Event {

private String eventId;
private String eventTitle;
private String eventCategory;
private String eventSubCategory;
private String eventDescription;
private String eventDate;
private String eventTime;
private String eventAddress;
private String eventCity;
private String eventCountry;
private String eventWebsite;
private String eventEmail;
private String eventPhone;
private String eventKeywords;

public Event()
{

}

// ALL GETS AND SETS

11-10 23:37:08.315: E/AndroidRuntime(5592): FATAL EXCEPTION: main
11-10 23:37:08.315: E/AndroidRuntime(5592): java.lang.NullPointerException
11-10 23:37:08.315: E/AndroidRuntime(5592):     at com.nxtldn.trill.EventSync.onPostExecute(EventSync.java:71)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at com.nxtldn.trill.EventSync.onPostExecute(EventSync.java:1)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at android.os.AsyncTask.finish(AsyncTask.java:631)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at android.os.AsyncTask.access$600(AsyncTask.java:177)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at android.os.Looper.loop(Looper.java:137)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at android.app.ActivityThread.main(ActivityThread.java:4745)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at java.lang.reflect.Method.invokeNative(Native Method)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at java.lang.reflect.Method.invoke(Method.java:511)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
11-10 23:37:08.315: E/AndroidRuntime(5592):     at dalvik.system.NativeStart.main(Native Method)