/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2000,2008 Oracle. All rights reserved.
*
* $Id: TupleTupleMarshalledBinding.java,v 12.8 2008/02/07 17:12:25 mark Exp $
*/
package com.sleepycat.bind.tuple;
import com.sleepycat.util.RuntimeExceptionWrapper;
/**
* A concrete TupleTupleBinding
that delegates to the
* MarshalledTupleEntry
and
* MarshalledTupleKeyEntity
interfaces of the entity class.
*
*
This class calls the methods of the {@link MarshalledTupleEntry} * interface to convert between the data entry and entity object. It calls the * methods of the {@link MarshalledTupleKeyEntity} interface to convert between * the key entry and the entity object. These two interfaces must both be * implemented by the entity class.
* * @author Mark Hayes */ public class TupleTupleMarshalledBinding extends TupleTupleBinding { private Class cls; /** * Creates a tuple-tuple marshalled binding object. * *The given class is used to instantiate entity objects using * {@link Class#forName}, and therefore must be a public class and have a * public no-arguments constructor. It must also implement the {@link * MarshalledTupleEntry} and {@link MarshalledTupleKeyEntity} * interfaces.
* * @param cls is the class of the entity objects. */ public TupleTupleMarshalledBinding(Class cls) { this.cls = cls; // The entity class will be used to instantiate the entity object. // if (!MarshalledTupleKeyEntity.class.isAssignableFrom(cls)) { throw new IllegalArgumentException(cls.toString() + " does not implement MarshalledTupleKeyEntity"); } if (!MarshalledTupleEntry.class.isAssignableFrom(cls)) { throw new IllegalArgumentException(cls.toString() + " does not implement MarshalledTupleEntry"); } } // javadoc is inherited public Object entryToObject(TupleInput keyInput, TupleInput dataInput) { // This "tricky" binding returns the stored data as the entity, but // first it sets the transient key fields from the stored key. MarshalledTupleEntry obj; try { obj = (MarshalledTupleEntry) cls.newInstance(); } catch (IllegalAccessException e) { throw new RuntimeExceptionWrapper(e); } catch (InstantiationException e) { throw new RuntimeExceptionWrapper(e); } if (dataInput != null) { // may be null if used by key extractor obj.unmarshalEntry(dataInput); } MarshalledTupleKeyEntity entity = (MarshalledTupleKeyEntity) obj; if (keyInput != null) { // may be null if used by key extractor entity.unmarshalPrimaryKey(keyInput); } return entity; } // javadoc is inherited public void objectToKey(Object object, TupleOutput output) { MarshalledTupleKeyEntity entity = (MarshalledTupleKeyEntity) object; entity.marshalPrimaryKey(output); } // javadoc is inherited public void objectToData(Object object, TupleOutput output) { MarshalledTupleEntry entity = (MarshalledTupleEntry) object; entity.marshalEntry(output); } }