Após o deploy com sucesso o Heroku gera erros ao exectutar a aplicação. Verifiquei o LOG, e encontrei estas mensagens:
2020-04-27T22:49:43.480370+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.catalina.core.StandardContext startInternal
2020-04-27T22:49:43.480378+00:00 app[web.1]: SEVERE: One or more listeners failed to start. Full details will be found in the appropriate container log file
2020-04-27T22:49:43.518342+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.catalina.core.StandardContext startInternal
2020-04-27T22:49:43.518344+00:00 app[web.1]: SEVERE: Context [] startup failed due to previous errors
2020-04-27T22:49:43.522912+00:00 app[web.1]: SEVERE: Context [] failed in [org.apache.catalina.core.StandardContext] lifecycle. Allowing Tomcat to shutdown.
2020-04-27T22:49:43.525037+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.catalina.core.ApplicationContext log
2020-04-27T22:49:43.525038+00:00 app[web.1]: INFO: Closing Spring root WebApplicationContext
2020-04-27T22:49:43.563920+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.catalina.loader.WebappClassLoaderBase clearReferencesJdbc
2020-04-27T22:49:43.563941+00:00 app[web.1]: WARNING: The web application [ROOT] registered the JDBC driver [com.mysql.cj.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
2020-04-27T22:49:43.564725+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.catalina.loader.WebappClassLoaderBase clearReferencesJdbc
2020-04-27T22:49:43.564726+00:00 app[web.1]: WARNING: The web application [ROOT] registered the JDBC driver [org.postgresql.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
2020-04-27T22:49:43.575284+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.catalina.loader.WebappClassLoaderBase clearReferencesThreads
2020-04-27T22:49:43.575287+00:00 app[web.1]: WARNING: The web application [ROOT] appears to have started a thread named [mysql-cj-abandoned-connection-cleanup] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
2020-04-27T22:49:43.575288+00:00 app[web.1]: java.lang.Object.wait(Native Method)
2020-04-27T22:49:43.575289+00:00 app[web.1]: java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:144)
2020-04-27T22:49:43.575290+00:00 app[web.1]: com.mysql.cj.jdbc.AbandonedConnectionCleanupThread.run(AbandonedConnectionCleanupThread.java:85)
2020-04-27T22:49:43.575290+00:00 app[web.1]: java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
2020-04-27T22:49:43.575291+00:00 app[web.1]: java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
2020-04-27T22:49:43.575291+00:00 app[web.1]: java.lang.Thread.run(Thread.java:748)
2020-04-27T22:49:43.587624+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.coyote.AbstractProtocol start
2020-04-27T22:49:43.587625+00:00 app[web.1]: INFO: Starting ProtocolHandler ["http-nio-8884"]
2020-04-27T22:49:43.599904+00:00 app[web.1]: Apr 27, 2020 10:49:43 PM org.apache.coyote.AbstractProtocol pause
2020-04-27T22:49:43.599906+00:00 app[web.1]: INFO: Pausing ProtocolHandler ["http-nio-8884"]
2020-04-27T22:49:43.861892+00:00 heroku[web.1]: State changed from up to crashedComo resolvo isso?
