/*
* JBoss, Home of Professional Open Source.
* Copyright 2006, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file 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
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* 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: http://www.fsf.org.
*/
package org.jboss.resource.adapter.jdbc.vendor;
import java.io.Serializable;
import java.lang.reflect.Method;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.ResultSet;
import org.jboss.logging.Logger;
import org.jboss.resource.adapter.jdbc.ValidConnectionChecker;
/**
* Implements check valid connection sql Requires MySQL driver 3.1.8 or later.
* This should work on just about any version of the database itself but will
* only be "fast" on version 3.22.1 and later. Prior to that version it just
* does "SELECT 1" anyhow.
*
* @author <a href="mailto:adrian@jboss.org">Adrian Brock</a>
* @author <a href="mailto:acoliver ot jbosss dat org">Andrew C. Oliver</a>
* @author <a href="mailto:jim.moran@jboss.org">Jim Moran</a>
* @version $Revision: 57189 $
*/
public class MySQLValidConnectionChecker implements ValidConnectionChecker, Serializable {
private static final long serialVersionUID = -2227528634302168878L;
private static final Logger log = Logger.getLogger(MySQLValidConnectionChecker.class);
private Method ping;
private boolean driverHasPingMethod = false;
// The timeout (apparently the timeout is ignored?)
private static Object[] params = new Object[] {};
public MySQLValidConnectionChecker() {
try {
Class mysqlConnection = Thread.currentThread().getContextClassLoader().loadClass("com.mysql.jdbc.Connection");
ping = mysqlConnection.getMethod("ping", new Class[] {});
if (ping != null) {
driverHasPingMethod = true;
}
} catch (Exception e) {
log.warn("Cannot resolve com.mysq.jdbc.Connection.ping method. Will use 'SELECT 1' instead.", e);
}
}
public SQLException isValidConnection(Connection c) {
//if there is a ping method then use it, otherwise just use a 'SELECT 1' statement
if (driverHasPingMethod) {
try {
ping.invoke(c, params);
} catch (Exception e) {
if (e instanceof SQLException) {
return (SQLException) e;
} else {
log.warn("Unexpected error in ping", e);
return new SQLException("ping failed: " + e.toString());
}
}
} else {
Statement stmt = null;
ResultSet rs = null;
try {
stmt = c.createStatement();
rs = stmt.executeQuery("SELECT 1");
} catch (Exception e) {
if (e instanceof SQLException) {
return (SQLException) e;
} else {
log.warn("Unexpected error in ping (SELECT 1)", e);
return new SQLException("ping (SELECT 1) failed: " + e.toString());
}
} finally {
//cleanup the Statment
try {
if (rs != null) rs.close();
if (stmt != null) stmt.close();
} catch (SQLException e) {
}
}
}
return null;
}
}
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