MySqlCommandDispatcher.java

/**
 * <pre>
 * 	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; either version 3 of the License, 
 * or (at your option) any later version. 
 * 
 * 	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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 * </pre>
 */
package com.meidusa.amoeba.mysql.handler;

import java.util.HashMap;
import java.util.Map;

import org.apache.log4j.Logger;

import com.meidusa.amoeba.context.ProxyRuntimeContext;
import com.meidusa.amoeba.mysql.net.MysqlClientConnection;
import com.meidusa.amoeba.mysql.net.packet.ErrorPacket;
import com.meidusa.amoeba.mysql.net.packet.ExecutePacket;
import com.meidusa.amoeba.mysql.net.packet.LongDataPacket;
import com.meidusa.amoeba.mysql.net.packet.MysqlPacketBuffer;
import com.meidusa.amoeba.mysql.net.packet.OkPacket;
import com.meidusa.amoeba.mysql.net.packet.QueryCommandPacket;
import com.meidusa.amoeba.net.Connection;
import com.meidusa.amoeba.net.MessageHandler;
import com.meidusa.amoeba.net.Sessionable;
import com.meidusa.amoeba.net.poolable.ObjectPool;
import com.meidusa.amoeba.route.QueryRouter;

/**
 * handler
 * 
 * @author <a href=mailto:piratebase@sina.com>Struct chen</a>
 */
public class MySqlCommandDispatcher implements MessageHandler {

    protected static Logger logger  = Logger.getLogger(MySqlCommandDispatcher.class);

    private static long     timeout = -1;

    private static byte[]   STATIC_OK_BUFFER;
    static {
        OkPacket ok = new OkPacket();
        ok.affectedRows = 0;
        ok.insertId = 0;
        ok.packetId = 1;
        ok.serverStatus = 2;
        STATIC_OK_BUFFER = ok.toByteBuffer(null).array();
    }

    public void handleMessage(Connection connection, byte[] message) {
        MysqlClientConnection conn = (MysqlClientConnection) connection;

        QueryCommandPacket command = new QueryCommandPacket();
        command.init(message, connection);
        try {
            if (MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_QUIT) || MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_STMT_CLOSE)) {
                if (logger.isDebugEnabled()) {
                    logger.debug(command);
                }
            } else if (MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_PING)) {
                conn.postMessage(STATIC_OK_BUFFER);
            } else if (MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_QUERY)) {
                QueryRouter router = ProxyRuntimeContext.getInstance().getQueryRouter();
                ObjectPool[] pools = router.doRoute(conn, command.query, false, null);
                if (pools == null) {
                    conn.postMessage(STATIC_OK_BUFFER);
                    return;
                }
                MessageHandler handler = new QueryCommandMessageHandler(conn, message, pools, timeout);
                if (handler instanceof Sessionable) {
                    Sessionable session = (Sessionable) handler;
                    try {
                        session.startSession();
                    } catch (Exception e) {
                        logger.error("start Session error:", e);
                        session.endSession();
                        throw e;
                    }
                }
            } else if (MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_STMT_PREPARE)) {
                PreparedStatmentInfo preparedInf = conn.getPreparedStatmentInfo(command.query);
                byte[] buffer = preparedInf.getByteBuffer();
                conn.postMessage(buffer);
                return;
            } else if (MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_STMT_SEND_LONG_DATA)) {
                conn.addLongData(message);
            } else if (MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_STMT_EXECUTE)) {
                long statmentId = ExecutePacket.readStatmentID(message);
                PreparedStatmentInfo preparedInf = conn.getPreparedStatmentInfo(statmentId);
                if (preparedInf == null) {
                    ErrorPacket error = new ErrorPacket();
                    error.errno = 1044;
                    error.packetId = 1;
                    error.sqlstate = "42000";
                    error.serverErrorMessage = "Unknown prepared statment id=" + statmentId;
                    conn.postMessage(error.toByteBuffer(connection).array());
                    logger.warn("Unknown prepared statment id:" + statmentId);
                } else {
                    Map<Integer, Object> longMap = new HashMap<Integer, Object>();
                    for (byte[] longdate : conn.getLongDataList()) {
                        LongDataPacket packet = new LongDataPacket();
                        packet.init(longdate, connection);
                        longMap.put(packet.parameterIndex, packet.data);
                    }

                    ExecutePacket executePacket = new ExecutePacket(preparedInf, longMap);
                    executePacket.init(message, connection);

                    QueryRouter router = ProxyRuntimeContext.getInstance().getQueryRouter();
                    ObjectPool[] pools = router.doRoute(conn, preparedInf.getPreparedStatment(), false, executePacket.getParameters());

                    PreparedStatmentExecuteMessageHandler handler = new PreparedStatmentExecuteMessageHandler(
                                                                                                              conn,
                                                                                                              preparedInf,
                                                                                                              message,
                                                                                                              pools,
                                                                                                              timeout);
                    if (handler instanceof Sessionable) {
                        Sessionable session = (Sessionable) handler;
                        try {
                            session.startSession();
                        } catch (Exception e) {
                            logger.error("start Session error:", e);
                            session.endSession();
                            throw e;
                        }
                    }
                }
            } else if (MysqlPacketBuffer.isPacketType(message, QueryCommandPacket.COM_INIT_DB)) {
                conn.setSchema(command.query);
                conn.postMessage(STATIC_OK_BUFFER);
            } else {
                ErrorPacket error = new ErrorPacket();
                error.errno = 1044;
                error.packetId = 1;
                error.sqlstate = "42000";
                error.serverErrorMessage = "can not use this command here!!";
                conn.postMessage(error.toByteBuffer(connection).array());
                logger.warn("unsupport packet:" + command);
            }
        } catch (Exception e) {
            ErrorPacket error = new ErrorPacket();
            error.errno = 1044;
            error.packetId = 1;
            error.sqlstate = "42000";
            error.serverErrorMessage = e.getMessage();
            conn.postMessage(error.toByteBuffer(connection).array());
            logger.error("messageDispate error", e);
        }
    }
}