org.eclipse.persistence.annotations.CacheIsolationType Maven / Gradle / Ivy
/*
* Copyright (c) 2011, 2024 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Gordon Yorke - initial API and implementation
package org.eclipse.persistence.annotations;
/**
* Options for how Entity instances should be shared within an EclipseLink Persistence Unit / ServerSession
* @see org.eclipse.persistence.descriptors.ClassDescriptor#setCacheIsolation(CacheIsolationType)
* @see Cache
* @author Gordon Yorke
* @since EclipseLink 2.2
*/
public enum CacheIsolationType {
// These enums are ordered with ascending protective requirements
// This is intentional and any additions/alterations should take that into account
/**
* Entity instances will be cached within the EntityManagerFactory/ServerSession level.
* Any user queries for shared cache instances (ie Read-Only query hint) will return an Entity
* instance that may be shared by multiple clients.
*
* This setting is the default isolation level.
*/
SHARED,
/**
* Entity state information will be cached in the shared cache but Entity
* instances will not be shared. Any user queries for shared cache instances
* (ie Read-Only query hint) will return a new Entity instance with the cached state.
* This will ensure the instance is protected from any concurrent
* state change.
*/
PROTECTED,
/**
* The Entity and its data are not stored in the shared cache but is
* isolated to the Persistence Context/UnitOfWork or
* IsolatedClientSession. This setting effectively disables second level
* caching for this entity and should be used when users do not want caching for
* a particular Entity.
*/
ISOLATED
}