Plusieurs packages et analyse du protocole mysql

Structure des messages de communication MySQL

类型	名字	描述
int5bdf4c78156c7953567bb5a0aef2fc53	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
intf35d6e602fd7d0f0edfa6f7d103c1b57	序列号
string	payload	报文体，长度即为前面指定的payload长度

Package ResultssetRow

Payload

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

Classe de package ResultsetRow

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";
    }

}

Package ColumnDefinition

Payload

lenenc_str     catalog
lenenc_str     schema
lenenc_str     table
lenenc_str     org_table
lenenc_str     name
lenenc_str     org_name
lenenc_int     length of fixed-length fields [0c]
2              character set
4              column length
1              type
2              flags
1              decimals
2              filler [00] [00]
  if command was COM_FIELD_LIST {
lenenc_int     length of default-values
string[$len]   default values
  }

Classe de package ColumnCount

public class ColumnDefinitionPacket extends MySQLPacket {
    private static final byte[] DEFAULT_CATALOG = "def".getBytes();
    private static final byte NEXT_LENGTH = 0x0c;
    private static final byte[] FILLER = { 00, 00 };

    public byte[] catalog = DEFAULT_CATALOG;// always "def"
    public byte[] schema;
    public byte[] table;
    public byte[] orgTable;
    public byte[] name;
    public byte[] orgName;
    public byte nextLength = NEXT_LENGTH;// always 0x0c
    public int charsetSet;
    public long length;
    public int type;
    public int flags;
    public byte decimals;
    public byte[] filler = FILLER;
    public byte[] defaultValues;

    public void read(byte[] data) {
        MySQLMessage mm = new MySQLMessage(data);
        this.packetLength = mm.readUB3();
        this.packetId = mm.read();
        this.catalog = mm.readBytesWithLength();
        this.schema = mm.readBytesWithLength();
        this.table = mm.readBytesWithLength();
        this.orgTable = mm.readBytesWithLength();
        this.name = mm.readBytesWithLength();
        this.orgName = mm.readBytesWithLength();
        this.nextLength = mm.read();
        this.charsetSet = mm.readUB2();
        this.length = mm.readUB4();
        this.type = mm.read() & 0xff;
        this.flags = mm.readUB2();
        this.decimals = mm.read();
        this.filler = mm.readBytes(2);
        if (mm.hasRemaining()) {
            this.defaultValues = mm.readBytesWithLength();
        }
    }

    @Override
    public void write(ByteBuffer buffer) {
        int size = calcPacketSize();
        BufferUtil.writeUB3(buffer, size);
        buffer.put(packetId);
        BufferUtil.writeWithLength(buffer, catalog, (byte) 0);
        BufferUtil.writeWithLength(buffer, schema, (byte) 0);
        BufferUtil.writeWithLength(buffer, table, (byte) 0);
        BufferUtil.writeWithLength(buffer, orgTable, (byte) 0);
        BufferUtil.writeWithLength(buffer, name, (byte) 0);
        BufferUtil.writeWithLength(buffer, orgName, (byte) 0);
        buffer.put(NEXT_LENGTH);
        BufferUtil.writeUB2(buffer, charsetSet);
        BufferUtil.writeUB4(buffer, length);
        buffer.put((byte) (type & 0xff));
        BufferUtil.writeUB2(buffer, flags);
        buffer.put(decimals);
        buffer.put(FILLER);
        if (defaultValues != null) {
            //only use for show columns
            BufferUtil.writeWithLength(buffer, defaultValues);
        }
    }

    @Override
    public int calcPacketSize() {
        int size = (catalog == null ? 1 : BufferUtil.getLength(catalog));
        size += (schema == null ? 1 : BufferUtil.getLength(schema));
        size += (table == null ? 1 : BufferUtil.getLength(table));
        size += (orgTable == null ? 1 : BufferUtil.getLength(orgTable));
        size += (name == null ? 1 : BufferUtil.getLength(name));
        size += (orgName == null ? 1 : BufferUtil.getLength(orgName));
        size += 13;
        if (defaultValues != null) {
            size += BufferUtil.getLength(defaultValues);
        }
        return size;
    }

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

}

Package ColumnCount

Charge utile

Protocol::LengthEncodedInteger

Classe de package ColumnCount

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";
    }

}