Java Code Examples for io.netty.buffer.ByteBuf#writeMediumLE()

public static void writeLengthEncodedInt(ByteBuf buf, Long n) {
	if (n == null) {
		buf.writeByte(NULL_VALUE);
	} else if (n < 0) {
		throw new IllegalArgumentException("Cannot encode a negative length: " + n);
	} else if (n < NULL_VALUE) {
		buf.writeByte(n.intValue());
	} else if (n < 0xffff) {
		buf.writeByte(SHORT_VALUE);
		buf.writeShortLE(n.intValue());
	} else if (n < 0xffffff) {
		buf.writeByte(MEDIUM_VALUE);
		buf.writeMediumLE(n.intValue());
	} else {
		buf.writeByte(LONG_VALUE);
		buf.writeLongLE(n);
	}
}
 

private void sendStatementPrepareCommand() {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_STMT_PREPARE);
  packet.writeCharSequence(cmd.sql(), encoder.encodingCharset);

  // set payload length
  int payloadLength = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, payloadLength);

  sendPacket(packet, payloadLength);
}
 

private void sendQueryCommand() {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_QUERY);
  packet.writeCharSequence(cmd.sql(), encoder.encodingCharset);

  // set payload length
  int payloadLength = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, payloadLength);

  sendPacket(packet, payloadLength);
}
 

private void sendInitDbCommand() {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_INIT_DB);
  packet.writeCharSequence(cmd.schemaName(), StandardCharsets.UTF_8);

  // set payload length
  int lenOfPayload = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, lenOfPayload);

  sendPacket(packet, lenOfPayload);
}
 

private void sendStatementFetchCommand(long statementId, int count) {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_STMT_FETCH);
  packet.writeIntLE((int) statementId);
  packet.writeIntLE(count);

  // set payload length
  int lenOfPayload = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, lenOfPayload);

  encoder.chctx.writeAndFlush(packet);
}
 

public static void writeLengthEncodedInteger(ByteBuf buffer, long value) {
  if (value < 251) {
    // 1-byte integer
    buffer.writeByte((byte) value);
  } else if (value <= 0xFFFF) {
    // 0xFC + 2-byte integer
    buffer.writeByte(0xFC);
    buffer.writeShortLE((int) value);
  } else if (value < 0xFFFFFF) {
    // 0xFD + 3-byte integer
    buffer.writeByte(0xFD);
    buffer.writeMediumLE((int) value);
  } else {
    // 0xFE + 8-byte integer
    buffer.writeByte(0xFE);
    buffer.writeLongLE(value);
  }
}
 

private void sendCloseStatementCommand(MySQLPreparedStatement statement) {
  ByteBuf packet = allocateBuffer(PAYLOAD_LENGTH + 4);
  // encode packet header
  packet.writeMediumLE(PAYLOAD_LENGTH);
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_STMT_CLOSE);
  packet.writeIntLE((int) statement.statementId);

  sendNonSplitPacket(packet);
}
 

private void sendSslRequest() {
  ByteBuf packet = allocateBuffer(36);
  // encode packet header
  packet.writeMediumLE(32);
  packet.writeByte(sequenceId);

  // encode SSLRequest payload
  packet.writeIntLE(encoder.clientCapabilitiesFlag);
  packet.writeIntLE(PACKET_PAYLOAD_LENGTH_LIMIT);
  packet.writeByte(cmd.collation().collationId());
  packet.writeZero(23); // filler

  sendNonSplitPacket(packet);
}
 

private Future<Void> sendFileInPacket(String filename, int offset, int length) {
  ByteBuf packetHeader = allocateBuffer(4);
  packetHeader.writeMediumLE(length);
  packetHeader.writeByte(sequenceId++);
  encoder.chctx.write(packetHeader);
  return encoder.socketConnection.socket().sendFile(filename, offset, length);
}
 

private void sendChangeUserCommand() {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_CHANGE_USER);
  BufferUtils.writeNullTerminatedString(packet, cmd.username(), StandardCharsets.UTF_8);
  String password = cmd.password();
  if (password.isEmpty()) {
    packet.writeByte(0);
  } else {
    packet.writeByte(password.length());
    packet.writeCharSequence(password, StandardCharsets.UTF_8);
  }
  BufferUtils.writeNullTerminatedString(packet, cmd.database(), StandardCharsets.UTF_8);
  MySQLCollation collation = cmd.collation();
  int collationId = collation.collationId();
  packet.writeShortLE(collationId);

  if ((encoder.clientCapabilitiesFlag & CLIENT_PLUGIN_AUTH) != 0) {
    BufferUtils.writeNullTerminatedString(packet, "mysql_native_password", StandardCharsets.UTF_8);
  }
  if ((encoder.clientCapabilitiesFlag & CLIENT_CONNECT_ATTRS) != 0) {
    Map<String, String> clientConnectionAttributes = cmd.connectionAttributes();
    if (clientConnectionAttributes != null) {
      encodeConnectionAttributes(clientConnectionAttributes, packet);
    }
  }

  // set payload length
  int lenOfPayload = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, lenOfPayload);

  sendPacket(packet, lenOfPayload);
}
 

final void sendBytesAsPacket(byte[] payload) {
  int payloadLength = payload.length;
  ByteBuf packet = allocateBuffer(payloadLength + 4);
  // encode packet header
  packet.writeMediumLE(payloadLength);
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeBytes(payload);

  sendNonSplitPacket(packet);
}
 

private void sendQuitCommand() {
  ByteBuf packet = allocateBuffer(PAYLOAD_LENGTH + 4);
  // encode packet header
  packet.writeMediumLE(PAYLOAD_LENGTH);
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_QUIT);

  sendNonSplitPacket(packet);
}
 

private void sendResetConnectionCommand() {
  ByteBuf packet = allocateBuffer(PAYLOAD_LENGTH + 4);
  // encode packet header
  packet.writeMediumLE(PAYLOAD_LENGTH);
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_RESET_CONNECTION);

  sendNonSplitPacket(packet);
}
 

private void sendStatementResetCommand(long statementId) {
  ByteBuf packet = allocateBuffer(PAYLOAD_LENGTH + 4);
  // encode packet header
  packet.writeMediumLE(PAYLOAD_LENGTH);
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_STMT_RESET);
  packet.writeIntLE((int) statementId);

  sendNonSplitPacket(packet);
}
 

private void encodeDateNParameter(ByteBuf payload, LocalDate date) {
  payload.writeByte(0x00);
  payload.writeByte(0x00);
  payload.writeByte(MSSQLDataTypeId.DATENTYPE_ID);
  if (date == null) {
    // null
    payload.writeByte(0);
  } else {
    payload.writeByte(3);
    long days = ChronoUnit.DAYS.between(MSSQLDataTypeCodec.START_DATE, date);
    payload.writeMediumLE((int) days);
  }
}
 

private void sendStatementExecuteCommand(MySQLPreparedStatement statement, boolean sendTypesToServer, Tuple params, byte cursorType) {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_STMT_EXECUTE);
  packet.writeIntLE((int) statement.statementId);
  packet.writeByte(cursorType);
  // iteration count, always 1
  packet.writeIntLE(1);

  int numOfParams = statement.bindingTypes().length;
  int bitmapLength = (numOfParams + 7) / 8;
  byte[] nullBitmap = new byte[bitmapLength];

  int pos = packet.writerIndex();

  if (numOfParams > 0) {
    // write a dummy bitmap first
    packet.writeBytes(nullBitmap);
    packet.writeBoolean(sendTypesToServer);

    if (sendTypesToServer) {
      for (DataType bindingType : statement.bindingTypes()) {
        packet.writeByte(bindingType.id);
        packet.writeByte(0); // parameter flag: signed
      }
    }

    for (int i = 0; i < numOfParams; i++) {
      Object value = params.getValue(i);
      if (value != null) {
        DataTypeCodec.encodeBinary(statement.bindingTypes()[i], value, encoder.encodingCharset, packet);
      } else {
        nullBitmap[i / 8] |= (1 << (i & 7));
      }
    }

    // padding null-bitmap content
    packet.setBytes(pos, nullBitmap);
  }

  // set payload length
  int payloadLength = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, payloadLength);

  sendPacket(packet, payloadLength);
}
 

private static void binaryEncodeInt3(Number value, ByteBuf buffer) {
  buffer.writeMediumLE(value.intValue());
}
 

private void sendBatchStatementExecuteCommand(MySQLPreparedStatement statement, Tuple params) {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  packet.writeByte(CommandType.COM_STMT_EXECUTE);
  packet.writeIntLE((int) statement.statementId);
  packet.writeByte(CURSOR_TYPE_NO_CURSOR);
  // iteration count, always 1
  packet.writeIntLE(1);

  /*
   * Null-bit map and type should always be reconstructed for every batch of parameters here
   */
  int numOfParams = statement.bindingTypes().length;
  int bitmapLength = (numOfParams + 7) / 8;
  byte[] nullBitmap = new byte[bitmapLength];

  int pos = packet.writerIndex();

  if (numOfParams > 0) {
    // write a dummy bitmap first
    packet.writeBytes(nullBitmap);
    packet.writeByte(1);
    for (int i = 0; i < params.size(); i++) {
      Object param = params.getValue(i);
      DataType dataType = DataTypeCodec.inferDataTypeByEncodingValue(param);
      packet.writeByte(dataType.id);
      packet.writeByte(0); // parameter flag: signed
    }

    for (int i = 0; i < numOfParams; i++) {
      Object value = params.getValue(i);
      if (value != null) {
        DataTypeCodec.encodeBinary(DataTypeCodec.inferDataTypeByEncodingValue(value), value, encoder.encodingCharset, packet);
      } else {
        nullBitmap[i / 8] |= (1 << (i & 7));
      }
    }

    // padding null-bitmap content
    packet.setBytes(pos, nullBitmap);
  }

  // set payload length
  int payloadLength = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, payloadLength);

  sendPacket(packet, payloadLength);
}
 

private void sendHandshakeResponseMessage(String username, String password, String database, byte[] nonce, String authMethodName, Map<String, String> clientConnectionAttributes) {
  ByteBuf packet = allocateBuffer();
  // encode packet header
  int packetStartIdx = packet.writerIndex();
  packet.writeMediumLE(0); // will set payload length later by calculation
  packet.writeByte(sequenceId);

  // encode packet payload
  int clientCapabilitiesFlags = encoder.clientCapabilitiesFlag;
  packet.writeIntLE(clientCapabilitiesFlags);
  packet.writeIntLE(PACKET_PAYLOAD_LENGTH_LIMIT);
  packet.writeByte(cmd.collation().collationId());
  packet.writeZero(23); // filler
  BufferUtils.writeNullTerminatedString(packet, username, StandardCharsets.UTF_8);
  if (password.isEmpty()) {
    packet.writeByte(0);
  } else {
    byte[] scrambledPassword;
    switch (authMethodName) {
      case "mysql_native_password":
        scrambledPassword = Native41Authenticator.encode(password.getBytes(StandardCharsets.UTF_8), nonce);
        break;
      case "caching_sha2_password":
        scrambledPassword = CachingSha2Authenticator.encode(password.getBytes(StandardCharsets.UTF_8), nonce);
        break;
      default:
        completionHandler.handle(CommandResponse.failure(new UnsupportedOperationException("Unsupported authentication method: " + authMethodName)));
        return;
    }
    if ((clientCapabilitiesFlags & CLIENT_PLUGIN_AUTH_LENENC_CLIENT_DATA) != 0) {
      BufferUtils.writeLengthEncodedInteger(packet, scrambledPassword.length);
      packet.writeBytes(scrambledPassword);
    } else if ((clientCapabilitiesFlags & CLIENT_SECURE_CONNECTION) != 0) {
      packet.writeByte(scrambledPassword.length);
      packet.writeBytes(scrambledPassword);
    } else {
      packet.writeByte(0);
    }
  }
  if ((clientCapabilitiesFlags & CLIENT_CONNECT_WITH_DB) != 0) {
    BufferUtils.writeNullTerminatedString(packet, database, StandardCharsets.UTF_8);
  }
  if ((clientCapabilitiesFlags & CLIENT_PLUGIN_AUTH) != 0) {
    BufferUtils.writeNullTerminatedString(packet, authMethodName, StandardCharsets.UTF_8);
  }
  if ((clientCapabilitiesFlags & CLIENT_CONNECT_ATTRS) != 0) {
    encodeConnectionAttributes(clientConnectionAttributes, packet);
  }

  // set payload length
  int payloadLength = packet.writerIndex() - packetStartIdx - 4;
  packet.setMediumLE(packetStartIdx, payloadLength);

  sendPacket(packet, payloadLength);
}
 

/**
 * Writes the 2-byte chunk length to the output buffer.将2字节块长度写入输出缓冲区。
 *
 * @param out The buffer to write to
 * @param chunkLength The length to write
 */
private static void writeChunkLength(ByteBuf out, int chunkLength) {
    out.writeMediumLE(chunkLength);
}