Re: com.mysql.jdbc.CommunicationsException due to java.io.EOFException...

[Andrew Trotter]

Hi,

I'm also experiencing this problem.

NOTE: I HAVEN'T SOLVED IT YET. I'M HOPING THE BELOW WILL.

using tomcat, mysql-connector-java-5.1.6, and Hibernate 3.something to access a mySQl db. if everything is left on overnight, the first connection fails, yet all following connections work fine.

To solve it, i've found a few things(I have yet to test them):

1) Placing these lines in your context.xml file:

<parameter><name>validationQuery</name><value>SELECT 1</value></parameter>
<parameter><name>testOnBorrow</name><value>true</value></parameter>
<parameter><name>testWhileIdle</name><value>true</value></parameter>
<parameter><name>timeBetweenEvictionRunsMillis</name><value>60000</value></parameter>
<parameter><name>numTestsPerEvictionRun</name><value>5</value></parameter>
<parameter><name>minEvictableIdleTimeMillis</name><value>600000</value></parameter>

The last 3 lines are to kill the connection so that it doesn't get quietly terminated(meaning tomcat doesn't notice there's no more connection and tries using it.) I'm most hopeful about these.


2) Placing autoReconnect=true in the database url, or as a parameter.

3) only applicable to hibernate users, add these to hibernate.cfg.xml:

<property name="connection.autoReconnect">true</property>
<property name="connection.autoReconnectForPools">true</property>
<property name="connection.is-connection-validation-required">true</property>

4) also Check classpath to see if any other versions of mySQl/connector-j are there.

5) there was mention of a firewall killing the connection after a certain time, but tomcat not noticing, then trying to use that connection. Doesn't apply to me, but I thought I'd mention it.

I hope this helps somebody. if nothing works, i'll have to keep looking for a solution.