javax.cache.expiry.ExpiryPolicy Maven / Gradle / Ivy
/**
* Copyright 2011-2016 Terracotta, Inc.
* Copyright 2011-2016 Oracle America Incorporated
*
* 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 javax.cache.expiry;
/**
* Defines functions to determine when cache entries will expire based on
* creation, access and modification operations.
*
* Each of the functions return a new {@link Duration} that specifies the
* amount of time that must pass before a cache entry is considered expired.
* {@link Duration} has constants defined for useful durations.
*
* @author Brian Oliver
* @author Greg Luck
* @since 1.0
* @see Duration
*/
public interface ExpiryPolicy {
/**
* Gets the {@link Duration} before a newly created Cache.Entry is considered
* expired.
*
* This method is called by a caching implementation after a Cache.Entry is
* created, but before a Cache.Entry is added to a cache, to determine the
* {@link Duration} before an entry expires. If a {@link Duration#ZERO}
* is returned the new Cache.Entry is considered to be already expired and
* will not be added to the Cache.
*
* Should an exception occur while determining the Duration, an implementation
* specific default {@link Duration} will be used.
*
* @return the new {@link Duration} before a created entry expires
*/
Duration getExpiryForCreation();
/**
* Gets the {@link Duration} before an accessed Cache.Entry is
* considered expired.
*
* This method is called by a caching implementation after a Cache.Entry is
* accessed to determine the {@link Duration} before an entry expires. If a
* {@link Duration#ZERO} is returned a Cache.Entry will be
* considered immediately expired. Returning null will result
* in no change to the previously understood expiry {@link Duration}.
*
* Should an exception occur while determining the Duration, an implementation
* specific default Duration will be used.
*
* @return the new {@link Duration} before an accessed entry expires
*/
Duration getExpiryForAccess();
/**
* Gets the {@link Duration} before an updated Cache.Entry is considered
* expired.
*
* This method is called by the caching implementation after a Cache.Entry is
* updated to determine the {@link Duration} before the updated entry expires.
* If a {@link Duration#ZERO} is returned a Cache.Entry is considered
* immediately expired. Returning null will result in no change
* to the previously understood expiry {@link Duration}.
*
* Should an exception occur while determining the Duration, an implementation
* specific default Duration will be used.
*
* @return the new {@link Duration} before an updated entry expires
*/
Duration getExpiryForUpdate();
}