How to get companion ads' height and width using exoplayer Ima extension?

Question

I want to get height and width of companion ads but every time app crashes. adEvent.getAd() returning ad but it crashes when I start null checking adEvent.getAd().getCompanionAds()

private class AdEventListener implements AdEvent.AdEventListener {

    @Override
    public void onAdEvent(AdEvent adEvent) {
        switch (adEvent.getType()) {
            case STARTED:
                companionViewGroup.setVisibility(View.VISIBLE);
                break;
            case ALL_ADS_COMPLETED:
                companionViewGroup.setVisibility(View.GONE);
                break;
            case LOADED:
                if (adEvent.getAd() != null 
                        && adEvent.getAd().getCompanionAds() != null) {
                    Log.d("TAG00", "height "+
                            adEvent.getAd().getCompanionAds().get(0).getHeight());
                }
                break;

        }
    }
}


E/AndroidRuntime: FATAL EXCEPTION: main
Process: <package_name>, PID: 3117
java.lang.NullPointerException: Attempt to invoke interface method 'java.util.Iterator java.util.List.iterator()' on a null object reference
at com.google.ads.interactivemedia.v3.impl.data.c.getCompanionAds(SourceFile:2)
at <package_name>.activities.PlayerActivity$d.onAdEvent(SourceFile:1077)
at com.google.ads.interactivemedia.v3.internal.dg.b(SourceFile:10)
at com.google.ads.interactivemedia.v3.internal.cv.b(SourceFile:15)
at com.google.ads.interactivemedia.v3.internal.ed.k(SourceFile:47)
at com.google.ads.interactivemedia.v3.internal.ej.f(SourceFile:5)
at com.google.ads.interactivemedia.v3.internal.eg.shouldOverrideUrlLoading(SourceFile:2)
at android.webkit.WebViewClient.shouldOverrideUrlLoading(WebViewClient.java:77)
at org.chromium.android_webview.AwContentsClientBridge.shouldOverrideUrlLoading(chromium-Monochrome.aab-stable-451515923:14)
at android.os.MessageQueue.nativePollOnce(Native Method)
at android.os.MessageQueue.next(MessageQueue.java:326)
at android.os.Looper.loop(Looper.java:160)
at android.app.ActivityThread.main(ActivityThread.java:6692)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)