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Process kill package and analysis of mysql protocol

黄舟
黄舟Original
2017-03-07 13:49:441039browse

git

https://github.com/sea-boat/mysql-protocol

Overview

The mysql client can use the process kill command to ask the server to terminate a connection. Normally, an ok packet will be returned.

mysql communication message structure

##string payloadMessage body, the length is the previously specified payload length
Type Name Description
int5bdf4c78156c7953567bb5a0aef2fc53 payload length Stored according to the least significant byte first, 3-byte payload and 1-byte sequence number combination Into the message header
intf35d6e602fd7d0f0edfa6f7d103c1b57 sequence number
process kill command package

Payload

1              [0c] COM_PROCCESS_KILL4              connection id

More details: http://dev.mysql.com/doc/internals/en/com-process-kill.html

process kill command package class

/**
 * 
 * <pre class="brush:php;toolbar:false"><b>mysql process kill packet.</b>
* @author *
seaboat
*
<b>email: </b>849586227@qq.com
*
<b>blog: </b>http://www.php.cn/;/pre>
 * @version 1.0
 * @see http://www.php.cn/
 */public class ProcessKillPacket extends MySQLPacket {

    public byte flag = (byte) 0xfe;    public int connectionId;    @Override
    public void read(byte[] data) {
        MySQLMessage mm = new MySQLMessage(data);
        packetLength = mm.readUB3();
        packetId = mm.read();
        flag = mm.read();
        connectionId = mm.readInt();
    }    @Override
    public void write(ByteBuffer buffer) {        int size = calcPacketSize();
        BufferUtil.writeUB3(buffer, size);
        buffer.put(packetId);
        buffer.put(COM_PROCESS_KILL);
        BufferUtil.writeInt(buffer, connectionId);
    }    @Override
    public int calcPacketSize() {        return 5;
    }    @Override
    protected String getPacketInfo() {        return "MySQL Process Kill Packet";
    }

}

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