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From John Huss <>
Subject Re: DataSourceInfo
Date Fri, 07 Aug 2015 14:30:27 GMT
I think this is a "feature" of MySQL.  It closes idle connections
eventually.  You can add a validationQuery to keep the connection active.

On Fri, Aug 7, 2015 at 2:40 AM Joe Baldwin <> wrote:

> Problem: I am having problems with MySQL connections being disabled
> improperly on the production server (the development server does not show
> the same error).  This happens only after an idle period (and only on the
> production server).
> Can not read response from server. Expected to read
> 4 bytes, read 0 bytes before connection was unexpectedly lost.
>         com.mysql.jdbc.MysqlIO.readFully(
> My theory is that there is some problem with the JDBC connector(s).  So I
> am trying to track down two separate issues
>         1. my development MySQL DBMS version is 5.6 while the production
> version is 5.5 (this may be the problem)
>         2. my webhost gives me only incremental access to tomcat, so I am
> attempting to verify the JDBC connector (I installed per their directions -
> webhost imposed).
> It is #2 that is what I want to start with, but it is difficult to
> verify.  I used to be able to accomplish #2 with Cayenne DataSourceInfo.
> However,
>         getJdbcDriver() now returns null
>         getUserName() now returns null
> and
>         getMaxConnections() now returns the wrong number
> This used to work a few versions back - so this is confusing. So,  I
> cannot tell at this point whether the DataSourceInfo is incorrect, or
> whether the file (I am using DHCP) is not being read
> correctly, or some other problem.
> So, I believe my first step is to get DataSourceInfo working again so that
> I can verify the correct JDBC driver is being used (there are two - as I
> said).
> Question:
> 1. is DataSourceInfo still a reliable way to get JDBC info?
> 2. if so, could you please show me a few lines of example code (because my
> code is failing) ?
> Thanks
> Joe

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