javax.cache.processor.MutableEntry 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.processor;
import javax.cache.Cache;
import javax.cache.integration.CacheLoader;
/**
* A mutable representation of a {@link javax.cache.Cache.Entry}.
*
* Mutable entries are used by {@link EntryProcessor}s to mutate
* {@link Cache.Entry}s in place, atomically.
*
* @param the type of key
* @param the type of value
*
* @author Greg Luck
* @since 1.0
* @see EntryProcessor
*/
public interface MutableEntry extends Cache.Entry {
/**
* Checks for the existence of the entry in the cache
*
* @return true if the entry exists
*/
boolean exists();
/**
* Removes the entry from the Cache.
*
* This has the same semantics as calling {@link Cache#remove}.
*/
void remove();
/**
* Returns the value stored in the cache.
*
* If the cache is configured to use read-through, and this method
* would return null because the entry is missing from the cache,
* the Cache's {@link CacheLoader} is called in an attempt to load
* the entry.
*
* @return the value corresponding to this entry
*/
V getValue();
/**
* Sets or replaces the value associated with the key.
*
* If {@link #exists} is false and setValue is called
* then a mapping is added to the cache visible once the EntryProcessor
* completes. Moreover a second invocation of {@link #exists()}
* will return true.
*
* @param value the value to update the entry with
* @throws ClassCastException if the implementation supports and is
* configured to perform runtime-type-checking,
* and value type is incompatible with that
* which has been configured for the
* {@link Cache}
*/
void setValue(V value);
}