oracle.toplink.essentials.descriptors.WrapperPolicy Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*/
// Copyright (c) 1998, 2007, Oracle. All rights reserved.
package oracle.toplink.essentials.descriptors;
import java.io.Serializable;
import oracle.toplink.essentials.exceptions.*;
import oracle.toplink.essentials.internal.sessions.AbstractSession;
/**
* Purpose: The wrapper policy can be used to wrap all objects read from the database in another object.
* This allows for TopLink to utilize one version of the class for its purposes and allows for the
* application to deal with another version of the object.
* The wrapper policy is used for things such as EJB Entity Beans and is directly used by the
* TopLink for WebLogic product for EJB Container Managed Persistence.
*
* It is assumed that relationships must be through the wrapper objects.
* Object identity is not maintained on the wrapper objects, only the wrapped object.
*/
public interface WrapperPolicy extends Serializable {
/**
* PUBLIC:
* Required: Lets the policy perform initialization.
* @param session the session to initialize against
*/
void initialize(AbstractSession session) throws DescriptorException;
/**
* PUBLIC:
* Required: Return true if the wrapped value should be traversed.
* Normally the wrapped value is looked after independently, it is not required to be traversed.
*/
boolean isTraversable();
/**
* PUBLIC:
* Required: Return true if the object is already wrapped.
*/
boolean isWrapped(Object object);
/**
* PUBLIC:
* Required: Set the descriptor.
* @param descriptor the descriptor for the object being wrapped
*/
void setDescriptor(ClassDescriptor descriptor);
/**
* PUBLIC:
* Required: Unwrap the object to return the implementation that is meant to be used by TopLink.
* The object may already be unwrapped in which case the object should be returned.
* @param proxy the wrapped object
* @param session the session to unwrap into
*/
Object unwrapObject(Object proxy, AbstractSession session);
/**
* PUBLIC:
* Required: Wrap the object to return the implementation that the application requires.
* The object may already be wrapped in which case the object should be returned.
* @param original, the object to be wrapped
* @param session the session to wrap the object against.
* @return java.lang.Object the wrapped object
*/
Object wrapObject(Object original, AbstractSession session);
}