mysql 协议的ResultsetRow包及解析

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";
}

}

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