/*
* Copyright 1999-2012 Alibaba Group.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.alibaba.cobar.jdbc.packet;
import com.alibaba.cobar.jdbc.util.MySQLMessage;
/**
* From server to client after command, if no error and result set -- that is,
* if the command was a query which returned a result set. The Result Set Header
* Packet is the first of several, possibly many, packets that the server sends
* for result sets. The order of packets for a result set is:
*
* <pre>
* (Result Set Header Packet) the number of columns
* (Field Packets) column descriptors
* (EOF Packet) marker: end of Field Packets
* (Row Data Packets) row contents
* (EOF Packet) marker: end of Data Packets
*
* Bytes Name
* ----- ----
* 1-9 (Length-Coded-Binary) field_count
* 1-9 (Length-Coded-Binary) extra
*
* @see http://forge.mysql.com/wiki/MySQL_Internals_ClientServer_Protocol#Result_Set_Header_Packet
* </pre>
*
* @author xianmao.hexm 2010-7-22 下午05:59:55
*/
public class ResultSetHeaderPacket extends MySQLPacket {
public int fieldCount;
public long extra;
public void read(BinaryPacket data) {
this.packetLength = data.packetLength;
this.packetId = data.packetId;
MySQLMessage mm = new MySQLMessage(data.value);
this.fieldCount = (int) mm.readLength();
if (mm.hasRemaining()) {
this.extra = mm.readLength();
}
}
@Override
protected String packetInfo() {
return "MySQL ResultSetHeader Packet";
}
}