com.hazelcast.internal.eviction.impl.strategy.AbstractEvictionStrategy Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2016, Hazelcast, Inc. All Rights Reserved.
*
* 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 com.hazelcast.internal.eviction.impl.strategy;
import com.hazelcast.internal.eviction.Evictable;
import com.hazelcast.internal.eviction.EvictableStore;
import com.hazelcast.internal.eviction.EvictionChecker;
import com.hazelcast.internal.eviction.EvictionListener;
import com.hazelcast.internal.eviction.EvictionPolicyEvaluator;
import com.hazelcast.internal.eviction.EvictionStrategy;
/**
* Base class for eviction implementations to evict {@link EvictableStore} implementations as specified
* {@link EvictionPolicyEvaluator}.
*/
public abstract class AbstractEvictionStrategy>
implements EvictionStrategy {
/**
* Does eviction if eviction is required by given {@link EvictionChecker}.
*
* @param evictableStore Store that holds {@link Evictable} entries
* @param evictionPolicyEvaluator {@link EvictionPolicyEvaluator} to evaluate
* {@link com.hazelcast.config.EvictionPolicy} on entries
* @param evictionChecker {@link EvictionChecker} to make a decision about if eviction is
* required or not. If you want evict anyway,
* you can use {@link EvictionChecker#EVICT_ALWAYS}
* @param evictionListener {@link EvictionListener} to listen evicted entries
*
* @return evicted entry count
*/
@Override
public int evict(S evictableStore, EvictionPolicyEvaluator evictionPolicyEvaluator,
EvictionChecker evictionChecker, EvictionListener evictionListener) {
if (evictionChecker != null) {
if (evictionChecker.isEvictionRequired()) {
return evictInternal(evictableStore, evictionPolicyEvaluator, evictionListener);
} else {
return 0;
}
} else {
return evictInternal(evictableStore, evictionPolicyEvaluator, evictionListener);
}
}
/**
* Does eviction internally.
*
* @param evictableStore Store that holds {@link Evictable} entries
* @param evictionPolicyEvaluator {@link EvictionPolicyEvaluator} to evaluate
* {@link com.hazelcast.config.EvictionPolicy} on entries
* @param evictionListener {@link EvictionListener} to listen evicted entries
*
* @return evicted entry count
*/
protected abstract int evictInternal(S evictableStore,
EvictionPolicyEvaluator evictionPolicyEvaluator,
EvictionListener evictionListener);
}