com.hazelcast.map.impl.EntryCostEstimator Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2021, 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.map.impl;
/**
* Owned entry cost estimator general contract.
*
* @param the type of key which's size going to be estimated.
* @param the type of key which's size going to be estimated.
*/
public interface EntryCostEstimator {
/**
* Returns the memory cost estimation so far
* @return the memory cost estimation so far
*/
long getEstimate();
/**
* Adjust the memory cost estimation by the given adjustment.
* The adjustmenet can be any negative or positive number.
*
* @param adjustment The delta by which the estimation will be adjusted
*/
void adjustEstimateBy(long adjustment);
/**
* Calculate the entry's value cost in memory
* @param value The entry's value
* @return The cost of this value in memory.
*/
long calculateValueCost(V value);
/**
* Calculate the entry's cost in memory
* @param key The key of the entry
* @param value The value of the entry
* @return The memory cost of this key/value pair, plus the entry structure itself.
*/
long calculateEntryCost(K key, V value);
/**
* Reset the current estimation to zero.
*/
void reset();
}