fieldpacket.java

mysql集群

/*
 * 	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.
 */
package com.meidusa.amoeba.mysql.net.packet;

import java.io.UnsupportedEncodingException;

import com.meidusa.amoeba.net.packet.AbstractPacketBuffer;

/**
 * 
 * @author <a href=mailto:[e-mail]>Struct chen</a>
 *
 */
public class FieldPacket extends AbstractPacket {
	public String catalog;
	public String db;
	public String table;
	public String orgTable;
	public String name;
	public String orgName;
	public int character;
	public long length;
	
	public transient String charsetName;
	/**
	 * mysql Type
	 */
	public byte type;
	
	/**
	 * javaType
	 */
	public transient int javaType;
	public int flags;
	public byte decimals;
	public String definition;
	@Override
	public void init(AbstractPacketBuffer myBuffer) {
		super.init(myBuffer);
		MysqlPacketBuffer buffer = (MysqlPacketBuffer)myBuffer;
		catalog = buffer.readLengthCodedString(CODE_PAGE_1252);
		db = buffer.readLengthCodedString(CODE_PAGE_1252);
		table = buffer.readLengthCodedString(CODE_PAGE_1252);
		orgTable = buffer.readLengthCodedString(CODE_PAGE_1252);
		name = buffer.readLengthCodedString(CODE_PAGE_1252);
		orgName = buffer.readLengthCodedString(CODE_PAGE_1252);
		buffer.readByte();//only for move position
		character = buffer.readInt();
		length = buffer.readLong();
		type = buffer.readByte();
		flags = buffer.readInt();
		decimals = buffer.readByte();
		buffer.readByte();
		buffer.readByte();
		if(buffer.getPosition()< buffer.getBufLength()){
			definition = buffer.readLengthCodedString(CODE_PAGE_1252);
		}
	}
	
	@Override
	protected void write2Buffer(AbstractPacketBuffer myBuffer) throws UnsupportedEncodingException {
		super.write2Buffer(myBuffer);
		MysqlPacketBuffer buffer = (MysqlPacketBuffer)myBuffer;
		buffer.writeLengthCodedString(catalog,CODE_PAGE_1252);
		
		buffer.writeLengthCodedString(db,CODE_PAGE_1252);
		buffer.writeLengthCodedString(table,CODE_PAGE_1252);
		buffer.writeLengthCodedString(orgTable,CODE_PAGE_1252);
		buffer.writeLengthCodedString(name,CODE_PAGE_1252);
		buffer.writeLengthCodedString(orgName,CODE_PAGE_1252);
		buffer.writeByte((byte)0x0c);//write filler
		buffer.writeInt(character);
		buffer.writeLong(length);
		buffer.writeByte(type);
		buffer.writeInt(flags);
		buffer.writeByte(decimals);
		buffer.writeByte((byte)0x00);
		buffer.writeByte((byte)0x00);
		buffer.writeLengthCodedString(definition,CODE_PAGE_1252);
		
	}

	protected int calculatePacketSize(){
		int packLength = super.calculatePacketSize();
		
		int length = (catalog ==null?0:catalog.length());
		length += (db ==null?0:db.length());
		length += (table ==null?0:table.length());
		length += (orgTable ==null?0:orgTable.length());
		length += (name ==null?0:name.length());
		length += (orgName ==null?0:orgName.length());
		length = length *2;
		length += 2+4+1+2+1+(definition ==null?0:definition.length())*2;
		
        packLength += length;
		return packLength;
	}

}