oracle.toplink.essentials.descriptors.WrapperPolicy Maven / Gradle / Ivy
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* // Copyright (c) 1998, 2007, Oracle. All rights reserved.
*
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
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);
}