mysql 协议的ResultsetRow包及解析

来源：互联网发布：范思哲男装淘宝编辑：程序博客网时间：2024/06/06 18:42

git

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

概况

ResultsetRow包属于服务端返回ResultSet时的其中一部分包，用于描述结果集的行记录。

mysql通信报文结构

类型名字描述 int<3> payload长度按照the least significant byte first存储，3个字节的payload和1个字节的序列号组合成报文头 int<1> 序列号 string payload 报文体，长度即为前面指定的payload长度

ResultsetRow包

Payload

if(NULL){  0xfb}else{  Protocol::LengthEncodedString}

更多详情： http://dev.mysql.com/doc/internals/en/com-query-response.html#text-resultset

ResultsetRow包类

/** *  * <pre><b>resultset row 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 ResultsetRowPacket extends MySQLPacket {    private static final byte NULL_MARK = (byte) 251;    public int columnCount;    public List<byte[]> columnValues;    public ResultsetRowPacket() {    }    public ResultsetRowPacket(int columnCount) {        this.columnCount = columnCount;    }    @Override    public void read(byte[] data) {        MySQLMessage mm = new MySQLMessage(data);        packetLength = mm.readUB3();        packetId = mm.read();        for (int i = 0; i < columnCount; i++) {            columnValues.add(mm.readBytesWithLength());        }    }    @Override    public void write(ByteBuffer buffer) {        BufferUtil.writeUB3(buffer, calcPacketSize());        buffer.put(packetId);        for (int i = 0; i < columnCount; i++) {            byte[] fv = columnValues.get(i);            if (fv == null) {                buffer.put(NULL_MARK);            } else {                BufferUtil.writeLength(buffer, fv.length);                buffer.put(fv);            }        }    }    @Override    public int calcPacketSize() {        int size = 0;        for (int i = 0; i < columnCount; i++) {            byte[] v = columnValues.get(i);            size += (v == null || v.length == 0) ? 1 : BufferUtil.getLength(v);        }        return size;    }    @Override    protected String getPacketInfo() {        return "MySQL Resultset Row Packet";    }}

1 0