/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2002,2008 Oracle. All rights reserved.
*
* $Id: DataValueAdapter.java,v 1.1 2008/02/07 17:12:26 mark Exp $
*/
package com.sleepycat.persist;
import com.sleepycat.bind.EntryBinding;
import com.sleepycat.db.DatabaseEntry;
/**
* A ValueAdapter where the "value" is the data, although the data in this case
* is the primary key in a KeysIndex.
*
* @author Mark Hayes
*/
class DataValueAdapter<V> implements ValueAdapter<V> {
private EntryBinding dataBinding;
DataValueAdapter(Class<V> keyClass, EntryBinding dataBinding) {
this.dataBinding = dataBinding;
}
public DatabaseEntry initKey() {
return new DatabaseEntry();
}
public DatabaseEntry initPKey() {
return null;
}
public DatabaseEntry initData() {
return new DatabaseEntry();
}
public void clearEntries(DatabaseEntry key,
DatabaseEntry pkey,
DatabaseEntry data) {
key.setData(null);
data.setData(null);
}
public V entryToValue(DatabaseEntry key,
DatabaseEntry pkey,
DatabaseEntry data) {
return (V) dataBinding.entryToObject(data);
}
public void valueToData(V value, DatabaseEntry data) {
throw new UnsupportedOperationException
("Cannot change the data in a key-only index");
}
}