I'm using DBCP 2.1.1 with POOL 2.4.3 (which are the latest releases as of a few minutes ago) to handle connections to MySQL databases. In my program I have code like this:
conn = ds.getConnection(); conn.clearWarnings(); if (conn.isValid(5)) Recently, I've been having problems where the connection is showing up as *not* valid, and I couldn't figure out why. My code uses conn.getWarnings() on invalid connections to try and determine why the connection is invalid, but it wasn't getting anything. No exception was being logged, so the return was likely null. The validation query is "SELECT 1". After scratching my head for a while, I decided to have the code run a "SELECT 1" query on the connection that reports invalid. As expected because the connection tests as invalid, that query failed, but the specific failure was surprising: Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed. How can a connection that I *just* retrieved from the pool be closed? The only thing that comes to mind is that I have configured idle connection eviction: opMaster.setTimeBetweenEvictionRunsMillis(Const.ONE_MINUTE); opMaster.setMinEvictableIdleTimeMillis(Const.ONE_MINUTE * 5); If the idle connection eviction is what's to blame for this (connection becomes invalid between the time it is retrieved and the validity is checked), it seems like that shouldn't be possible. Before I open an issue in Jira, I would like to know if there's anything I can add to my code (logging, info retrieval, etc) to check what might be going wrong -- try to confirm my theory that idle connection eviction is to blame. If that is indeed the problem, I would comment that getConnection() on the datasource should probably reset the idle timer so that the connection will not be quickly closed/pruned. Thanks, Shawn --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@commons.apache.org For additional commands, e-mail: user-h...@commons.apache.org
