Volley onErrorResponse Give NullPointerException

Question

I am trying to use the volleyball library in an android application.

this is my magazine

    10-31 14:30:09.277: E/AndroidRuntime(22916): java.lang.NullPointerException
10-31 14:30:09.277: E/AndroidRuntime(22916):    at com.mypackage.api.Api$2.onErrorResponse(Api.java:269)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at com.android.volley.Request.deliverError(Request.java:517)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:101)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at android.os.Handler.handleCallback(Handler.java:615)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at android.os.Handler.dispatchMessage(Handler.java:92)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at android.os.Looper.loop(Looper.java:137)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at android.app.ActivityThread.main(ActivityThread.java:4745)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at java.lang.reflect.Method.invokeNative(Native Method)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at java.lang.reflect.Method.invoke(Method.java:511)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-31 14:30:09.277: E/AndroidRuntime(22916):    at dalvik.system.NativeStart.main(Native Method)

this is how i use volley

    GetStringRequest req = new GetStringRequest(Request.Method.GET,URL_API,
    new Response.Listener<String>() {
    // handle success response
    }, new Response.ErrorListener() {
    //handle error response
    @Override
public void onErrorResponse(VolleyError volleyError) {

    try {
        String error = new String(volleyError.networkResponse.data, HTTP.UTF_8);
        }
        catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
        e.printStackTrace();
        }
    });

sometimes i get nullPointerException error on this line (269)

String error = new String(volleyError.networkResponse.data, HTTP.UTF_8);

I do not know what is wrong, does anyone know?

Answer 1

Most likely volleyError.networkResponse.data is empty. I'm not sure what you are trying to get with this line of code, but working with Volley and want to see what is in volleyError. You can try the following:

String error =  volleyError.toString();

- [ , , ]. VolleyErrors , API, -, , .. , , , , .

Answer 2

, onErrorResponse -

onErrorResponse null ( )

  new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                    if(error.getMessage==NULL){
  Toast.makeText(cardview.this, "Failed to retrieve data", Toast.LENGTH_LONG).show();
                    }
                else{
                        Toast.makeText(cardview.this, error.getMessage().toString(), Toast.LENGTH_LONG).show();
                    }

                });

.. ... , nullpointer .

Answer 3

Apply this code in the hope that it will help

@Override public void onErrorResponse (VolleyError volleyError) {

  Log.v("VolleyError",volleyError.getMessage);

});

This will result in a print error in your log.