/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
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 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Sep 5, 2007
*/
package com.bigdata.rawstore;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
/**
* An abstract base class for {@link IRawStore} implementations that use an
* append only (Write Once, Read Many) strategy. The {@link IAddressManager}
* interface is delegated to an {@link WormAddressManager} allowing flexible
* configuration of the use of bits to represent the byte offset of a record in
* the store and the bits used to represent the size of a record in the store.
*
* @see WormAddressManager
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
abstract public class AbstractRawWormStore extends AbstractRawStore implements IWORM {
/**
* The object that knows how to encode, decode, and (de-)serialize
* addresses.
*/
protected final WormAddressManager am;
/**
* The object that knows how to encode, decode, and (de-)serialize
* addresses.
*/
public final WormAddressManager getAddressManager() {
return am;
}
/**
* The #of bits out of a 64-bit long integer that are used to encode the
* byte offset as an unsigned integer. The remaining bits are used to
* encode the byte count (aka record length) as an unsigned integer.
*/
public final int getOffsetBits() {
return am.offsetBits;
}
/**
* @param offsetBits
* The #of bits that will be used to represent the byte offset in
* the 64-bit long integer addresses for the store. See
* {@link WormAddressManager}.
*/
public AbstractRawWormStore(final int offsetBits) {
super();
this.am = new WormAddressManager(offsetBits);
}
/*
* IAddressManager
*/
final public long toAddr(final int nbytes, final long offset) {
return am.toAddr(nbytes, offset);
}
final public long getOffset(final long addr) {
return am.getOffset(addr);
}
final public long getPhysicalAddress(final long addr) {
return am.getPhysicalAddress(addr);
}
final public int getByteCount(final long addr) {
return am.getByteCount(addr);
}
// final public void packAddr(final DataOutput out, final long addr)
// throws IOException {
//
// am.packAddr(out, addr);
//
// }
//
// final public long unpackAddr(final DataInput in) throws IOException {
//
// return am.unpackAddr(in);
//
// }
final public String toString(final long addr) {
return am.toString(addr);
}
}