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From: "lfgcampos (@lfgcampos)" <noreply+lfgcampos@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Fri, 06 Jun 2025 10:12:19 +0000
Subject: Re: [pgjdbc/pgjdbc] issue #3530: JDBC Shared Timer set to cancelled
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We faced an outage related to this (my assumption) when we upgraded from `42.7.4` to `42.7.6`.

Stacktrace is as follow:
```
Caused by: java.lang.IllegalStateException: Timer already cancelled.
	at java.base/java.util.Timer.sched(Unknown Source)
	at java.base/java.util.Timer.schedule(Unknown Source)
	at org.postgresql.jdbc.PgConnection.addTimerTask(PgConnection.java:1363)
	at org.postgresql.jdbc.PgStatement.startTimer(PgStatement.java:993)
	at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:517)
	at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:435)
	at org.postgresql.jdbc.PgPreparedStatement.executeWithFlags(PgPreparedStatement.java:196)
	at org.postgresql.jdbc.PgPreparedStatement.execute(PgPreparedStatement.java:182)
```

we are still investigating but sharing this earlier in case it helps anything!
as soon as I get more info, I will update here as well

----

update1:

I also found this on our logs, which seems somehow related

```
NullPointerException
Cannot read the array length because the return value of "org.postgresql.util.internal.Nullness.castNonNull(Object)" is null
...
org.postgresql.core.QueryExecutorBase in sendQueryCancel at line 199
org.postgresql.jdbc.PgConnection in cancelQuery at line 1220
org.postgresql.jdbc.PgStatement in cancel at line 926
org.postgresql.jdbc.PgStatement in cancelIfStillNeeded at line 1003
org.postgresql.jdbc.StatementCancelTimerTask in run at line 36
java.util.TimerThread in mainLoop
java.util.TimerThread in run
```