/*
* #!
* Ontopia Engine
* #-
* Copyright (C) 2001 - 2013 The Ontopia Project
* #-
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* !#
*/
package net.ontopia.persistence.proxy;
/**
* INTERNAL: Interface used to represent data store object
* identity. The identity has two parts; the type of object and an
* ordered list of primary key components. Note that an identity
* instance should always be immutable.
*
* Warning: Implementations of this class must all have the same
* hashCode() behaviour.
*/
public interface IdentityIF extends Cloneable {
/**
* INTERNAL: Returns the type of object. The returned value
* indicates the classification of the identified object. See also
* {@link PersistentIF#_p_getType()}.
*/
public Class<?> getType();
/**
* INTERNAL: Returns the number of primary key components that the
* identity has.
*/
public int getWidth();
/**
* INTERNAL: Returns the primary key component with the specified index.
*/
public Object getKey(int index);
/**
* INTERNAL: Creates an object instance of the type defined by this
* identity.
*/
public Object createInstance() throws Exception;
// FIXME: Consider moving this method elsewhere.
public Object clone();
}