Version 8

    What happens to JBoss if I restart the database?


    You can configure the following in your -ds.xml


    <valid-connection-checker-class-name>[see [jboss]/docs/examples/jca/[mydb]-ds.xml]</valid-connection-checker-class-name>

    JBoss will use the jdbc drivers ping operation to check the connection.  If the ping fails the connection will be destroyed/closed and new ones will be created. The valid-connection-checker-class-name must implement the following ValidConnectionChecker interface:


    * JBoss, Home of Professional Open Source
    * Copyright 2005, JBoss Inc., and individual contributors as indicated
    * by the @authors tag. See the copyright.txt in the distribution for a
    * full listing of individual contributors.
    * This is free software; you can redistribute it and/or modify it
    * under the terms of the GNU Lesser General Public License as
    * published by the Free Software Foundation; either version 2.1 of
    * the License, or (at your option) any later version.
    * This software is distributed in the hope that it will be useful,
    * but WITHOUT ANY WARRANTY; without even the implied warranty of
    * Lesser General Public License for more details.
    * You should have received a copy of the GNU Lesser General Public
    * License along with this software; if not, write to the Free
    * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
    * 02110-1301 USA, or see the FSF site:
    package org.jboss.resource.adapter.jdbc;
    import java.sql.Connection;
    import java.sql.SQLException;
     * Checks that a connection is valid
     * @author <a href="">Adrian Brock</a>
     * @version $Revision: $
    public interface ValidConnectionChecker
        * Checks the connection is valid
        * @param c the connection
        * @return Exception when not valid, null when valid
       SQLException isValidConnection(Connection c);



    OR you can use:


    <check-valid-connection-sql>some cheap sql statement</check-valid-connection-sql>
    e.g. for Oracle "select 1 from dual"

    JBoss will run the SQL statement before handing out the connection from the pool. If the SQL fails, the connection will be destroyed/closed and new ones will be created.


    <check-valid-connection> SQL for Sybase:

    If you are using


    select @@VERSION


    with Sybase, then it may not always work. See this for details