com.mysql.cj.protocol.a.ResultsetRowReader Maven / Gradle / Ivy
/*
* Copyright (c) 2016, 2020, Oracle and/or its affiliates.
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License, version 2.0, as published by the
* Free Software Foundation.
*
* This program is also distributed with certain software (including but not
* limited to OpenSSL) that is licensed under separate terms, as designated in a
* particular file or component or in included license documentation. The
* authors of MySQL hereby grant you an additional permission to link the
* program and your derivative works with the separately licensed software that
* they have included with MySQL.
*
* Without limiting anything contained in the foregoing, this file, which is
* part of MySQL Connector/J, is also subject to the Universal FOSS Exception,
* version 1.0, a copy of which can be found at
* http://oss.oracle.com/licenses/universal-foss-exception.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0,
* for more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package com.mysql.cj.protocol.a;
import java.io.IOException;
import java.util.Optional;
import com.mysql.cj.conf.PropertyKey;
import com.mysql.cj.conf.PropertySet;
import com.mysql.cj.conf.RuntimeProperty;
import com.mysql.cj.protocol.ProtocolEntityFactory;
import com.mysql.cj.protocol.ProtocolEntityReader;
import com.mysql.cj.protocol.ResultsetRow;
public class ResultsetRowReader implements ProtocolEntityReader {
protected NativeProtocol protocol;
protected PropertySet propertySet;
protected RuntimeProperty useBufferRowSizeThreshold;
public ResultsetRowReader(NativeProtocol prot) {
this.protocol = prot;
this.propertySet = this.protocol.getPropertySet();
this.useBufferRowSizeThreshold = this.propertySet.getMemorySizeProperty(PropertyKey.largeRowSizeThreshold);
}
/**
* Retrieve one row from the MySQL server. Note: this method is not
* thread-safe, but it is only called from methods that are guarded by
* synchronizing on this object.
*
* @param sf
* ProtocolEntityFactory
* @throws IOException
* if an error occurs
*/
@Override
public ResultsetRow read(ProtocolEntityFactory sf) throws IOException {
AbstractRowFactory rf = (AbstractRowFactory) sf;
NativePacketPayload rowPacket = null;
NativePacketHeader hdr = this.protocol.getPacketReader().readHeader();
// read the entire packet(s)
rowPacket = this.protocol.getPacketReader()
.readMessage(rf.canReuseRowPacketForBufferRow() ? Optional.ofNullable(this.protocol.getReusablePacket()) : Optional.empty(), hdr);
this.protocol.checkErrorMessage(rowPacket);
// Didn't read an error, so re-position to beginning of packet in order to read result set data
rowPacket.setPosition(rowPacket.getPosition() - 1);
// exit early with null if there's an EOF packet
if (!this.protocol.getServerSession().isEOFDeprecated() && rowPacket.isEOFPacket()
|| this.protocol.getServerSession().isEOFDeprecated() && rowPacket.isResultSetOKPacket()) {
this.protocol.readServerStatusForResultSets(rowPacket, true);
return null;
}
return sf.createFromMessage(rowPacket);
}
}