org.voltdb.PrivateVoltTableFactory Maven / Gradle / Ivy
/* This file is part of VoltDB.
* Copyright (C) 2008-2018 VoltDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with VoltDB. If not, see .
*/
package org.voltdb;
import java.nio.ByteBuffer;
/**
* Deliberately awkward access to package-private constructors of
* VoltTable. End users shouldn't call the constructors, but VoltDB
* needs to call them from many packages. By going through this proxy,
* it makes it very hard for someone to unintentionally call them.
*
*/
public abstract class PrivateVoltTableFactory {
public static VoltTable createUninitializedVoltTable() {
return new VoltTable();
}
public static VoltTable createVoltTableFromBuffer(ByteBuffer backing, boolean readOnly) {
return new VoltTable(backing, readOnly);
}
public static VoltTable createVoltTableFromSharedBuffer(ByteBuffer shared) {
VoltTable vt = new VoltTable();
vt.initFromBuffer(shared);
return vt;
}
public static VoltTable createVoltTableFromByteArray(byte[] backingBuff, int position, int len) {
VoltTable vt = new VoltTable();
vt.initFromByteArray(backingBuff, position, len);
return vt;
}
/**
* End users should not call this method.
* Obtain a reference to the table's underlying buffer.
* The returned reference's position and mark are independent of
* the table's buffer position and mark. The returned buffer has
* no mark and is at position 0.
*/
public static ByteBuffer getTableDataReference(VoltTable vt) {
ByteBuffer buf = vt.m_buffer.duplicate();
buf.rewind();
return buf;
}
public static byte[] getSchemaBytes(VoltTable vt) {
if (vt.getRowCount() > 0) {
throw new RuntimeException("getSchemaBytes() Only works if the table is empty");
}
ByteBuffer dup = vt.m_buffer.duplicate();
dup.limit(dup.limit() - 4);
dup.position(0);
byte retvalBytes[] = new byte[dup.remaining()];
dup.get(retvalBytes);
return retvalBytes;
}
/**
* End users should not call this method.
* @return Underlying buffer size
*/
public static int getUnderlyingBufferSize(VoltTable vt) {
return vt.m_buffer.position();
}
}