We use Firebase a ton at DripStat. So I am sad to see firebase basically not giving a flying f**k about their Java SDK.
Your web applications can no longer shut down
The Firebase SDK creates background non-daemon threads, so when you try to shutdown your apache tomcat using the ./shutdown.sh script, it wont. Your tomcat will continue running until you manually use the kill command on the process to kill it.
Deployment processes get screwed
Any tool/script that executes ./shutdown.sh on your tomcat server to kill it, will result in crazy errors cause while the script will execute and think tomcat is terminated that won’t in fact be the case. Tomcat will continue running until its manually terminated as described above.
Even in development, an extra step to remember
It even screws your development, since no longer does pressing the ‘Stop’ button in Intellij terminate Tomcat. You have to remember to 'kill’ tomcat using a separate button after you press the stop button.
Website has no info
Not only that, the website has no changelog or version history of their sdk artifact making it impossible to know when the sdk is updated and with what changes.
Conclusion
It is surprising that Firebase has completely ignored such a major issue which impacts both development and production time continuous delivery processes.