Why is the app not working on heroku?

Question

Java

I'm trying to upload a telegram bot on spring boot to heroku, the application itself works fine when launched from idea or through launching .jar, but I'm deploying on heroku for the first time and I don't understand what's wrong ..
The log itself from heroku:

2021-01-26T08:06:37.796116+00:00 heroku[worker.1]: Process exited with status 1
2021-01-26T08:06:37.507439+00:00 app[worker.1]: Picked up JAVA_TOOL_OPTIONS: -XX:+UseContainerSupport -Xmx300m -Xss512k -XX:CICompilerCount=2 -Dfile.encoding=UTF-8 
2021-01-26T08:06:37.742986+00:00 app[worker.1]: Error: Could not find or load main class App
2021-01-26T08:06:37.743037+00:00 app[worker.1]: Caused by: java.lang.ClassNotFoundException: App
2021-01-26T08:06:37.834066+00:00 heroku[worker.1]: State changed from up to crashed

Answer 1

Create an App class, write the main method there.

Answer 2

You need MutationObserver