source: Ballon/out/artifacts/geisa_artifact/WEB-INF/lib/mysql-connector-java-5.1.21/src/com/mysql/jdbc/jdbc2/optional/MysqlPooledConnection.java @ 848

/*
 Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved.
 

  The MySQL Connector/J is licensed under the terms of the GPLv2
  <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors.
  There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
  this software, see the FLOSS License Exception
  <http://www.mysql.com/about/legal/licensing/foss-exception.html>.

  This program is free software; you can redistribute it and/or modify it under the terms
  of the GNU General Public License as published by the Free Software Foundation; version 2
  of the License.

  This program 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 General Public License for more details.

  You should have received a copy of the GNU General Public License along with this
  program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth
  Floor, Boston, MA 02110-1301  USA

 */

package com.mysql.jdbc.jdbc2.optional;

import java.lang.reflect.Constructor;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import javax.sql.ConnectionEvent;
import javax.sql.ConnectionEventListener;
import javax.sql.PooledConnection;

import com.mysql.jdbc.ExceptionInterceptor;
import com.mysql.jdbc.SQLError;
import com.mysql.jdbc.Util;

/**
 * This class is used to wrap and return a physical connection within a logical
 * handle. It also registers and notifies ConnectionEventListeners of any
 * ConnectionEvents
 * 
 * @see javax.sql.PooledConnection
 * @see org.gjt.mm.mysql.jdbc2.optional.LogicalHandle
 * @author Todd Wolff <todd.wolff_at_prodigy.net>
 */
public class MysqlPooledConnection implements PooledConnection {

        private static final Constructor<?> JDBC_4_POOLED_CONNECTION_WRAPPER_CTOR;

        static {
                if (Util.isJdbc4()) {
                        try {
                                JDBC_4_POOLED_CONNECTION_WRAPPER_CTOR = Class.forName(
                                                "com.mysql.jdbc.jdbc2.optional.JDBC4MysqlPooledConnection")
                                                .getConstructor(
                                                                new Class[] { com.mysql.jdbc.Connection.class });
                        } catch (SecurityException e) {
                                throw new RuntimeException(e);
                        } catch (NoSuchMethodException e) {
                                throw new RuntimeException(e);
                        } catch (ClassNotFoundException e) {
                                throw new RuntimeException(e);
                        }
                } else {
                        JDBC_4_POOLED_CONNECTION_WRAPPER_CTOR = null;
                }
        }

        protected static MysqlPooledConnection getInstance(com.mysql.jdbc.Connection connection) throws SQLException {
                if (!Util.isJdbc4()) {
                        return new MysqlPooledConnection(connection);
                }

                return (MysqlPooledConnection) Util.handleNewInstance(
                                JDBC_4_POOLED_CONNECTION_WRAPPER_CTOR, new Object[] {
                                                connection}, connection.getExceptionInterceptor());
        }
        
        /**
         * The flag for an exception being thrown.
         */
        public static final int CONNECTION_ERROR_EVENT = 1;

        /**
         * The flag for a connection being closed.
         */
        public static final int CONNECTION_CLOSED_EVENT = 2;

        // ~ Instance/static variables .............................................

        private Map<ConnectionEventListener, ConnectionEventListener> connectionEventListeners;

        private Connection logicalHandle;

        private com.mysql.jdbc.Connection physicalConn;
        
        private ExceptionInterceptor exceptionInterceptor;

        // ~ Constructors ..........................................................

        /**
         * Construct a new MysqlPooledConnection and set instance variables
         * 
         * @param connection
         *            physical connection to db
         */
        public MysqlPooledConnection(com.mysql.jdbc.Connection connection) {
                this.logicalHandle = null;
                this.physicalConn = connection;
                this.connectionEventListeners = new HashMap<ConnectionEventListener, ConnectionEventListener>();
                this.exceptionInterceptor = this.physicalConn.getExceptionInterceptor();
        }

        /**
         * Adds ConnectionEventListeners to a hash table to be used for notification
         * of ConnectionEvents
         * 
         * @param connectioneventlistener
         *            listener to be notified with ConnectionEvents
         */
        public synchronized void addConnectionEventListener(
                        ConnectionEventListener connectioneventlistener) {

                if (this.connectionEventListeners != null) {
                        this.connectionEventListeners.put(connectioneventlistener,
                                        connectioneventlistener);
                }
        }

        /**
         * Removes ConnectionEventListeners from hash table used for notification of
         * ConnectionEvents
         * 
         * @param connectioneventlistener
         *            listener to be removed
         */
        public synchronized void removeConnectionEventListener(
                        ConnectionEventListener connectioneventlistener) {

                if (this.connectionEventListeners != null) {
                        this.connectionEventListeners.remove(connectioneventlistener);
                }
        }

        /**
         * Invoked by the container. Return a logicalHandle object that wraps a
         * physical connection.
         * 
         * @see java.sql.DataSource#getConnection()
         */
        public synchronized Connection getConnection() throws SQLException {
                return getConnection(true, false);
                
        }
        
        protected synchronized Connection getConnection(boolean resetServerState, 
                        boolean forXa)
                throws SQLException {
                if (this.physicalConn == null) {

                        SQLException sqlException = SQLError.createSQLException(
                                        "Physical Connection doesn't exist", this.exceptionInterceptor);
                        callConnectionEventListeners(CONNECTION_ERROR_EVENT, sqlException);

                        throw sqlException;
                }

                try {

                        if (this.logicalHandle != null) {
                                ((ConnectionWrapper) this.logicalHandle).close(false);
                        }

                        if (resetServerState) {
                                this.physicalConn.resetServerState();
                        }

                        this.logicalHandle = ConnectionWrapper.getInstance(this, 
                                        this.physicalConn, 
                                        forXa);
                } catch (SQLException sqlException) {
                        callConnectionEventListeners(CONNECTION_ERROR_EVENT, sqlException);

                        throw sqlException;
                }

                return this.logicalHandle;
        }

        /**
         * Invoked by the container (not the client), and should close the physical
         * connection. This will be called if the pool is destroyed or the
         * connectionEventListener receives a connectionErrorOccurred event.
         * 
         * @see java.sql.DataSource#close()
         */
        public synchronized void close() throws SQLException {
                if (this.physicalConn != null) {
                        this.physicalConn.close();
                        
                        this.physicalConn = null;
                }
                
                if (this.connectionEventListeners != null) {
                        this.connectionEventListeners.clear();
                        
                        this.connectionEventListeners = null;
                }
        }

        /**
         * Notifies all registered ConnectionEventListeners of ConnectionEvents.
         * Instantiates a new ConnectionEvent which wraps sqlException and invokes
         * either connectionClose or connectionErrorOccurred on listener as
         * appropriate.
         * 
         * @param eventType
         *            value indicating whether connectionClosed or
         *            connectionErrorOccurred called
         * @param sqlException
         *            the exception being thrown
         */
        protected synchronized void callConnectionEventListeners(int eventType,
                        SQLException sqlException) {

                if (this.connectionEventListeners == null) {

                        return;
                }

                Iterator<Map.Entry<ConnectionEventListener, ConnectionEventListener>> iterator = this.connectionEventListeners.entrySet().iterator();
                
                ConnectionEvent connectionevent = new ConnectionEvent(this,
                                sqlException);

                while (iterator.hasNext()) {

                        ConnectionEventListener connectioneventlistener = iterator.next().getValue();

                        if (eventType == CONNECTION_CLOSED_EVENT) {
                                connectioneventlistener.connectionClosed(connectionevent);
                        } else if (eventType == CONNECTION_ERROR_EVENT) {
                                connectioneventlistener
                                                .connectionErrorOccurred(connectionevent);
                        }
                }
        }
        
        protected ExceptionInterceptor getExceptionInterceptor() {
                return this.exceptionInterceptor;
        }
}