DB connection leaks

Problem Statement

We are seeing some new leaking connections on startup which might be causing db deadlocks or other issues. Here is one example report:

java.lang.Exception: Apparent connection leak detected
	at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:100)
	at com.dotmarketing.db.DbConnectionFactory.getConnection(DbConnectionFactory.java:253)
	at com.dotmarketing.common.db.DotConnect.executeQuery(DotConnect.java:625)
	at com.dotmarketing.common.db.DotConnect.loadResult(DotConnect.java:334)
	at com.dotmarketing.common.db.DotConnect.loadResults(DotConnect.java:456)
	at com.dotmarketing.servlets.UpdateQuartzCronJobsServlet.init(UpdateQuartzCronJobsServlet.java:48)
	at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:986)
	at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:943)
	at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:840)
	at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4222)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:4523)

Steps to Reproduce

Start dotCMS , tail the logs

Acceptance Criteria

• No more db leaks

dotCMS Version

26.03.20

Severity

Medium - Some functionality impacted

Links

https://dotcms.slack.com/archives/C096E0QAM7G/p1774457832731549

Start by reproducing the issue by starting dotCMS and tailing the logs. Trace the reported startup path through UpdateQuartzCronJobsServlet.init, DotConnect, and DbConnectionFactory, using the HikariDataSource stack trace as the guide. Done means the reported startup connection leaks no longer appear in the logs.