com.hazelcast.map.EntryLoader 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;
import static com.hazelcast.internal.util.Preconditions.isNotNull;
/**
* This is an extension to {@link MapLoader}. Entries loaded by EntryLoader
* may have expiration times attached to them. In that case, the entry
* is removed after given expiration time.
*
* See {@link MapLoader}.
*
* @param type of the EntryLoader key
* @param type of the EnyryLoader value
*/
public interface EntryLoader extends MapLoader> {
/**
* Represents a value with an expiration time attached to it.
* Expiration time is optional.
* @param the type of the value object
*/
class MetadataAwareValue {
/**
* Represents no expiration time for a particular value
*/
public static final long NO_TIME_SET = Long.MAX_VALUE;
private final V value;
private final long expirationTime;
/**
* Creates a value without attaching an expiration time
* @param value the value
*/
public MetadataAwareValue(V value) {
this.value = isNotNull(value, "value");
this.expirationTime = NO_TIME_SET;
}
/**
* Creates a value and attaches an expiration time to it.
* See {@link #getExpirationTime()} for how expiration time
* is defined.
*
* @param value the value
* @param expirationTime expiration time associated with the value
*/
public MetadataAwareValue(V value, long expirationTime) {
this.value = isNotNull(value, "value");
this.expirationTime = expirationTime;
}
/**
* Returns the value
* @return the value
*/
public V getValue() {
return value;
}
/**
* The expiration date of this entry. The entry is removed from
* maps after the specified date. This value overrides any expiration
* time calculated by using ttl and idle time configurations, both
* per key and per map configurations.
*
* @return the difference, measured in milliseconds, between
* the expiration time and midnight, January 1, 1970 UTC.
*/
public long getExpirationTime() {
return expirationTime;
}
}
}