/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2000,2008 Oracle. All rights reserved.
*
* $Id: TupleTupleBinding.java,v 12.7 2008/01/08 20:58:36 bostic Exp $
*/
package com.sleepycat.bind.tuple;
import com.sleepycat.bind.EntityBinding;
import com.sleepycat.db.DatabaseEntry;
/**
* An abstract EntityBinding
that treats an entity's key entry and
* data entry as tuples.
*
*
This class takes care of converting the entries to/from {@link
* TupleInput} and {@link TupleOutput} objects. Its three abstract methods
* must be implemented by a concrete subclass to convert between tuples and
* entity objects.
*
* - {@link #entryToObject(TupleInput,TupleInput)}
* - {@link #objectToKey(Object,TupleOutput)}
* - {@link #objectToData(Object,TupleOutput)}
*
*
* @author Mark Hayes
*/
public abstract class TupleTupleBinding extends TupleBase
implements EntityBinding {
/**
* Creates a tuple-tuple entity binding.
*/
public TupleTupleBinding() {
}
// javadoc is inherited
public Object entryToObject(DatabaseEntry key, DatabaseEntry data) {
return entryToObject(TupleBinding.entryToInput(key),
TupleBinding.entryToInput(data));
}
// javadoc is inherited
public void objectToKey(Object object, DatabaseEntry key) {
TupleOutput output = getTupleOutput(object);
objectToKey(object, output);
outputToEntry(output, key);
}
// javadoc is inherited
public void objectToData(Object object, DatabaseEntry data) {
TupleOutput output = getTupleOutput(object);
objectToData(object, output);
outputToEntry(output, data);
}
// abstract methods
/**
* Constructs an entity object from {@link TupleInput} key and data
* entries.
*
* @param keyInput is the {@link TupleInput} key entry object.
*
* @param dataInput is the {@link TupleInput} data entry object.
*
* @return the entity object constructed from the key and data.
*/
public abstract Object entryToObject(TupleInput keyInput,
TupleInput dataInput);
/**
* Extracts a key tuple from an entity object.
*
* @param object is the entity object.
*
* @param output is the {@link TupleOutput} to which the key should be
* written.
*/
public abstract void objectToKey(Object object, TupleOutput output);
/**
* Extracts a key tuple from an entity object.
*
* @param object is the entity object.
*
* @param output is the {@link TupleOutput} to which the data should be
* written.
*/
public abstract void objectToData(Object object, TupleOutput output);
}