/*
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 May 28, 2008
*/
package com.bigdata.btree;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.Properties;
import com.bigdata.btree.keys.ASCIIKeyBuilderFactory;
import com.bigdata.btree.keys.DefaultKeyBuilderFactory;
import com.bigdata.btree.keys.IKeyBuilder;
import com.bigdata.btree.keys.IKeyBuilderFactory;
import com.bigdata.btree.keys.KeyBuilder;
/**
* Default implementation uses the {@link KeyBuilder} to format the object as a
* key and requires that the values are byte[]s which it passes on without
* change. Deserialization of the tuple value always the byte[] itself.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public class NOPTupleSerializer extends DefaultTupleSerializer {
/**
*
*/
private static final long serialVersionUID = 2211020411074955099L;
public static transient final ITupleSerializer INSTANCE = new NOPTupleSerializer(
new DefaultKeyBuilderFactory(new Properties()));
/**
* De-serialization ctor.
*/
public NOPTupleSerializer() {
}
/**
* Normally callers will use an {@link ASCIIKeyBuilderFactory} since
* Unicode support is not required
* @param keyBuilderFactory
*
* @see ASCIIKeyBuilderFactory
*/
public NOPTupleSerializer(final IKeyBuilderFactory keyBuilderFactory) {
super(keyBuilderFactory);
}
/**
* {@inheritDoc}
*
* Return <i>obj</i> iff it is a <code>byte[]</code> and otherwise converts
* <i>obj</i> to a byte[] using {@link IKeyBuilder#append(Object)}.
*/
@Override
public byte[] serializeKey(Object obj) {
if (obj == null)
throw new IllegalArgumentException();
if(obj instanceof byte[]) {
return (byte[]) obj;
}
return getKeyBuilder().reset().append(obj).getKey();
}
@Override
public byte[] serializeVal(Object obj) {
return (byte[])obj;
}
@Override
public Object deserialize(ITuple tuple) {
if (tuple == null)
throw new IllegalArgumentException();
return tuple.getValue();
}
/**
* This is an unsupported operation. Additional information is required to
* either decode the internal unsigned byte[] keys or to extract the key
* from the de-serialized value (if it is being stored in that value). You
* can either write your own {@link ITupleSerializer} or you can specialize
* this one so that it can de-serialize your keys using whichever approach
* makes the most sense for your data.
*
* @throws UnsupportedOperationException
* always.
*/
public Object deserializeKey(ITuple tuple) {
throw new UnsupportedOperationException();
}
/**
* The initial version (no additional persistent state).
*/
private final static transient byte VERSION0 = 0;
/**
* The current version.
*/
private final static transient byte VERSION = VERSION0;
public void readExternal(final ObjectInput in) throws IOException,
ClassNotFoundException {
super.readExternal(in);
final byte version = in.readByte();
switch (version) {
case VERSION0:
break;
default:
throw new UnsupportedOperationException("Unknown version: "
+ version);
}
}
public void writeExternal(final ObjectOutput out) throws IOException {
super.writeExternal(out);
out.writeByte(VERSION);
}
}