org.eclipse.persistence.annotations.Cache Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation
EclipseLink build based upon Git transaction f2b9fc5
The newest version!
/*
 * Copyright (c) 1998, 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:
//     Oracle - initial API and implementation from Oracle TopLink
package org.eclipse.persistence.annotations;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * The Cache annotation is used to configure the EclipseLink object cache.
 * By default, EclipseLink uses a shared object cache to cache all objects.
 * The caching type and options can be configured on a per-class basis to allow
 * optimal caching.
 * This includes options for configuring the type of caching,
 * setting the size, disabling the shared cache, expiring objects, refreshing,
 * and cache coordination (clustering).
 * 
 * A Cache annotation may be defined on an Entity or MappedSuperclass. In the
 * case of inheritance, a Cache annotation should only be defined on the root
 * of the inheritance hierarchy.
 *
 * @see CacheType
 * @see CacheCoordinationType
 *
 * @see org.eclipse.persistence.descriptors.ClassDescriptor
 * @see org.eclipse.persistence.descriptors.invalidation.CacheInvalidationPolicy
 *
 * @author Guy Pelletier
 * @since Oracle TopLink 11.1.1.0.0
 */
@Target({TYPE})
@Retention(RUNTIME)
public @interface Cache {
    /**
     * The type of cache to use.
     * 

     * The default is {@linkplain CacheType#SOFT_WEAK}.
     */
    CacheType type() default CacheType.SOFT_WEAK;

    /**
     * The size of cache to use.
     * 

     * The default is 100.
     */
    int size() default 100;

    /**
     * Controls the level of caching this Entity will use.
     * 

     * The default is {@linkplain CacheIsolationType#SHARED} which has EclipseLink
     * Caching all Entities in the Shared Cache.
     * @see CacheIsolationType
     */
    CacheIsolationType isolation() default CacheIsolationType.SHARED;

    /**
     * Expire cached instance after a fix period of time (ms).
     * Queries executed against the cache after this will be forced back
     * to the database for a refreshed copy.
     * 

     * By default, there is no expiry.
     */
    int expiry() default -1; // minus one is no expiry.

    /**
     * Expire cached instance a specific time of day. Queries
     * executed against the cache after this will be forced back to the
     * database for a refreshed copy.
     */
    TimeOfDay expiryTimeOfDay() default @TimeOfDay(specified=false);

    /**
     * Force all queries that go to the database to always
     * refresh the cache.
     * Consider disabling the shared cache instead of forcing refreshing.
     * 

     * Default is false.
     */
    boolean alwaysRefresh() default false;

    /**
     * For all queries that go to the database, refresh the cache
     * only if the data received from the database by a query is newer than
     * the data in the cache (as determined by the optimistic locking field).
     * This is normally used in conjunction with alwaysRefresh, and by itself
     * it only affects explicit refresh calls or queries.
     * 

     * Default is false.
     */
    boolean refreshOnlyIfNewer() default false;

    /**
     * Setting to true will force all queries to bypass the
     * cache for hits but still resolve against the cache for identity.
     * This forces all queries to hit the database.
     */
    boolean disableHits() default false;

    /**
     * The cache coordination mode.
     * 

     * Note that cache coordination must also be configured for the persistence unit/session.
     */
    CacheCoordinationType coordinationType() default CacheCoordinationType.SEND_OBJECT_CHANGES;

    /**
     * The database change notification mode.
     * 
     * Note that database event listener must also be configured for the persistence unit/session.
     */
    DatabaseChangeNotificationType databaseChangeNotificationType() default DatabaseChangeNotificationType.INVALIDATE;
}