mysql 协议的ColumnCount包及解析

git

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

概况

ColumnCount包属于服务端返回ResultSet时的其中一部分包。

mysql通信报文结构

ColumnCount包

Payload

Protocol::LengthEncodedInteger

更多详情 ： http://dev.mysql.com/doc/internals/en/com-query-response.html#packet-ProtocolText::ResultsetRow

ColumnCount包类

/**
 *
 * <pre><b>column count packet.</b></pre>
 * @author
 * <pre>seaboat</pre>
 * <pre><b>email: </b>849586227@qq.com</pre>
 * <pre><b>blog: </b>http://blog.csdn.net/wangyangzhizhou</pre>
 * @version 1.0
 * @see http://dev.mysql.com/doc/internals/en/com-query-response.html#text-resultset
 */
public class ColumnCountPacket extends MySQLPacket {

    public int columnCount;

    public void read(byte[] data) {
        MySQLMessage mm = new MySQLMessage(data);
        this.packetLength = mm.readUB3();
        this.packetId = mm.read();
        this.columnCount = (int) mm.readLength();
    }

    @Override
    public void write(ByteBuffer buffer) {
        int size = calcPacketSize();
        BufferUtil.writeUB3(buffer, size);
        buffer.put(packetId);
        BufferUtil.writeLength(buffer, columnCount);
    }

    @Override
    public int calcPacketSize() {
        int size = BufferUtil.getLength(columnCount);
        return size;
    }

    @Override
    protected String getPacketInfo() {
        return "MySQL Column Count Packet";
    }

}

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