com.talent.mysql.packet.factory.MysqlHeaderFactory.java Source code

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Here is the source code for com.talent.mysql.packet.factory.MysqlHeaderFactory.java

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/*
 * Copyright (c) 2013, OpenCloudDB/MyCAT and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software;Designed and Developed mainly by many Chinese 
 * opensource volunteers. you can redistribute it and/or modify it under the 
 * terms of the GNU General Public License version 2 only, as published by the
 * Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 * 
 * Any questions about this component can be directed to it's project Web address 
 * https://code.google.com/p/opencloudb/.
 *
 */
package com.talent.mysql.packet.factory;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;

import java.nio.ByteOrder;
import java.util.NoSuchElementException;

import org.apache.commons.pool2.ObjectPool;
import org.apache.commons.pool2.impl.GenericObjectPool;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 
 * @filename:    com.talent.mysql.packet.factory.MysqlHeaderFactory
 * @copyright:   Copyright (c)2010
 * @company:     talent
 * @author:      
 * @version:     1.0
 * @create time: 20131227 ?9:16:56
 * @record
 * <table cellPadding="3" cellSpacing="0" style="width:600px">
 * <thead style="font-weight:bold;background-color:#e3e197">
 *    <tr>   <td>date</td>   <td>author</td>      <td>version</td>   <td>description</td></tr>
 * </thead>
 * <tbody style="background-color:#ffffeb">
 *    <tr><td>20131227</td>   <td></td>   <td>1.0</td>   <td>create</td></tr>
 * </tbody>
 * </table>
 */
public class MysqlHeaderFactory {
    private static Logger log = LoggerFactory.getLogger(MysqlHeaderFactory.class);

    /**
     * 
     */
    private MysqlHeaderFactory() {

    }

    private static ObjectPool<MysqlHeader> objectPool = new GenericObjectPool<MysqlHeader>(
            new MysqlHeaderPoolFactory());

    public static MysqlHeader borrow() {
        try {
            MysqlHeader mysqlHeader = objectPool.borrowObject();
            log.warn("borrow obj {}", mysqlHeader);
            return mysqlHeader;
        } catch (Exception e) {
            log.error("borrow obj fail", e);
            return new MysqlHeader();
        }
    }

    public static MysqlHeader borrow(int bodyLength, byte serialNum) {
        try {
            MysqlHeader mysqlHeader = borrow();
            log.warn("borrow obj {}", mysqlHeader);
            mysqlHeader.setBodyLength(bodyLength);
            mysqlHeader.setSerialNum(serialNum);
            return mysqlHeader;
        } catch (Exception e) {
            log.error("borrow obj fail", e);
            return new MysqlHeader(bodyLength, serialNum);
        }
    }

    public static void returnObj(MysqlHeader mysqlHeader) {
        try {
            log.warn("return obj {}", mysqlHeader);
            objectPool.returnObject(mysqlHeader);
        } catch (Exception e) {
            log.error("return obj fail", e);
        }
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        int bodyLength = 9;
        byte serialNum = 2;
        MysqlHeader mysqlHeader = new MysqlHeader(bodyLength, serialNum);
        ByteBuf byteBuf = mysqlHeader.encode();
        byteBuf.readerIndex(0);
        mysqlHeader.decode(byteBuf);
    }

    public static class MysqlHeader {
        private static Logger log = LoggerFactory.getLogger(MysqlHeader.class);

        public static final int HEADER_LEN = 4;

        private MysqlHeader(int bodyLength, byte serialNum) {
            super();
            this.bodyLength = bodyLength;
            this.serialNum = serialNum;
        }

        /**
         * 
         */
        MysqlHeader() {

        }

        private int bodyLength = 0;

        private byte serialNum = 0;

        public ByteBuf encode() {
            ByteBuf _byteBuf = Unpooled.buffer(bodyLength + HEADER_LEN);
            ByteBuf byteBuf = _byteBuf.order(ByteOrder.LITTLE_ENDIAN);

            boolean xx = _byteBuf == byteBuf;

            byteBuf.setInt(0, bodyLength);
            byteBuf.setByte(3, serialNum);
            byteBuf.writerIndex(byteBuf.capacity());
            byteBuf.readerIndex(4);
            return byteBuf;
        }

        public void decode(ByteBuf byteBuf) {
            byteBuf = byteBuf.order(ByteOrder.LITTLE_ENDIAN);

            ByteBuf lengthBuf = Unpooled.buffer(4);
            lengthBuf = lengthBuf.order(ByteOrder.LITTLE_ENDIAN);

            byteBuf.getBytes(byteBuf.readerIndex(), lengthBuf, 3);
            bodyLength = lengthBuf.getInt(0);
            serialNum = byteBuf.getByte(byteBuf.readerIndex() + 3);
            byteBuf.writerIndex(byteBuf.capacity());
            byteBuf.readerIndex(byteBuf.readerIndex() + 3);
        }

        public int getBodyLength() {
            return bodyLength;
        }

        public void setBodyLength(int bodyLength) {
            this.bodyLength = bodyLength;
        }

        public byte getSerialNum() {
            return serialNum;
        }

        public void setSerialNum(byte serialNum) {
            this.serialNum = serialNum;
        }
    }
}