Provide FixedAdsLoader to play ads from URLs known in advance

I found out that someone post about how to play ads locally through this link [https://github.com/google/ExoPlayer/issues/3664](url) . However, it not show the code in details how to implement ads loader without ima extension. As solution, I found this link helpfully to use [https://www.programcreek.com/java-api-examples/?code=googleads/googleads-ima-android/googleads-ima-android-master/BasicExample/app/src/main/java/com/google/ads/interactivemedia/v3/samples/videoplayerapp/MyActivity.java](url) and this link to play ads multline (meaning that every 30 seconds play the ads) [https://stackoverflow.com/questions/49871348/how-to-show-ads-at-specific-points-using-exoplayers-ima-extension](url). If someone know how to customize adsloader without ima extension please share the code. Thank you.