匿名通过本文主要向大家介绍了mysql ，FieldList，命令包等相关知识,希望本文的分享对您有所帮助
git
https://github.com/sea-boat/mysql-protocol
概况
当mysql客户端使用show column命令时即对应这个FieldList命令包。
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 |
FieldList命令包
Payload
1 [04] COM_FIELD_LISTstring[NUL] tablestring[EOF] field wildcard
更多详情 ： http://dev.mysql.com/doc/internals/en/com-field-list.html
FieldList命令包操作
FieldList命令包类
/**
*
* <pre><b>mysql field list packet.</b></pre>
* @author
* <pre>seaboat</pre>
* <pre><b>email: </b>849586227@qq.com</pre>
* <pre><b>blog: </b>http:///;/pre>
* @version 1.0
* @see http:///
*/public class FieldListPacket extends MySQLPacket {
public byte flag; public byte[] table; public byte[] fieldWildcard; @Override
public void read(byte[] data) {
MySQLMessage mm = new MySQLMessage(data);
packetLength = mm.readUB3();
packetId = mm.read();
flag = mm.read();
table = mm.readBytesWithNull();
fieldWildcard = mm.readBytes();
} @Override
public void write(ByteBuffer buffer) {
BufferUtil.writeUB3(buffer, calcPacketSize());
buffer.put(packetId);
buffer.put(COM_FIELD_LIST);
BufferUtil.writeWithNull(buffer, table);
buffer.put(fieldWildcard);
} @Override
public int calcPacketSize() { int i = 1;
i += table.length + 1;
i += fieldWildcard.length; return i;
} @Override
protected String getPacketInfo() { return "MySQL Field List Packet";
}
}以上就是详细介绍mysql 协议的FieldList命令包及解析的内容，更多相关内容请关注微课江湖（）！