ColumnDefinition-Paket und Parsing-Codedetails des MySQL-Protokolls

git

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

Übersicht

Das ColumnDefinition-Paket ist Teil des Pakets, wenn der Server das ResultSet zurückgibt, und wird zur Beschreibung der Feldinformationen des Ergebnissatzes verwendet.

MySQL-Kommunikationsnachrichtenstruktur

Typ	Name	Beschreibung th >
int5bdf4c78156c7953567bb5a0aef2fc53	Payload-Länge	wird entsprechend dem niedrigstwertigen Byte zuerst, 3 Wörter, gespeichert Die Nutzlast der Strophe und die 1-Byte-Sequenznummer werden zu einem Nachrichtenheader zusammengefasst
intf35d6e602fd7d0f0edfa6f7d103c1b57	Seriennummer

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

Zeichenfolge Nutzlast Nachrichtentext, die Länge ist die zuvor angegebene Nutzlastlänge tr>

ColumnDefinition Package

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 set4              
column length1              
type2              
flags1              
decimals2              
filler [00] [00]  if command was COM_FIELD_LIST {
lenenc_int     
length of default-valuesstring[$len]   
default values
  }

Weitere Details: http: / /dev.mysql.com/doc/internals/en/com-query-response.html#column-definition

ColumnCount-Paketklasse

/**
 * 
 * <pre class="brush:php;toolbar:false"><b>column definition command packet.</b>

* @author *

seaboat

*

<b>email: </b>849586227@qq.com

*

<b>blog: </b>http://www.php.cn/;/pre>
 * @version 1.0
 * @see http://www.php.cn/
 */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";
    }

}

Das Obige ist das ColumnDefinition-Paket von Das MySQL-Protokoll und Weitere Informationen zum Parsen des Codes finden Sie auf der chinesischen PHP-Website (www.php.cn) für weitere verwandte Inhalte!