com.hazelcast.map.impl.event.MapEventPublisher Maven / Gradle / Ivy

/*
 * Copyright (c) 2008-2018, 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.event;

import com.hazelcast.core.EntryEventType;
import com.hazelcast.core.EntryView;
import com.hazelcast.nio.Address;
import com.hazelcast.nio.serialization.Data;
import com.hazelcast.util.Clock;

/**
 * Helper methods for publishing events related to map actions. The implementation may delegate
 * to other parts of the system, for instance the WAN or event subsystem.
 *
 * @see MapEventPublisherImpl
 */
public interface MapEventPublisher {

    /**
     * Notifies the WAN subsystem of a map update on a replica owner.
     *
     * @param mapName   the map name
     * @param entryView the updated entry
     */
    void publishWanReplicationUpdate(String mapName, EntryView entryView);

    /**
     * Notifies the WAN subsystem of a map entry removal on a replica owner.
     *
     * @param mapName    the map name
     * @param key        the key of the removed entry
     * @param removeTime the clock time for the remove event
     * @see Clock#currentTimeMillis()
     */
    void publishWanReplicationRemove(String mapName, Data key, long removeTime);

    /**
     * Notifies the WAN subsystem of a map update on a backup replica.
     *
     * @param mapName   the map name
     * @param entryView the updated entry
     */
    void publishWanReplicationUpdateBackup(String mapName, EntryView entryView);

    /**
     * Notifies the WAN subsystem of a map entry removal on a backup replica.
     *
     * @param mapName    the map name
     * @param key        the key of the removed entry
     * @param removeTime the clock time for the remove event
     * @see Clock#currentTimeMillis()
     */
    void publishWanReplicationRemoveBackup(String mapName, Data key, long removeTime);

    void publishMapEvent(Address caller, String mapName, EntryEventType eventType, int numberOfEntriesAffected);

    /**
     * Publish an event to the event subsystem.
     *
     * @param caller       the address of the caller that caused the event
     * @param mapName      the map name
     * @param eventType    the event type
     * @param dataKey      the key of the event map entry
     * @param dataOldValue the old value of the map entry
     * @param dataValue    the new value of the map entry
     */
    void publishEvent(Address caller, String mapName, EntryEventType eventType, Data dataKey, Object dataOldValue,
                      Object dataValue);

    /**
     * Publish an event to the event subsystem. This method can be used for a merge event since
     * it also accepts the value which was used in the merge process.
     *
     * @param caller           the address of the caller that caused the event
     * @param mapName          the map name
     * @param eventType        the event type
     * @param dataKey          the key of the event map entry
     * @param dataOldValue     the old value of the map entry
     * @param dataValue        the new value of the map entry
     * @param dataMergingValue the value used when performing a merge operation in case of a {@link EntryEventType#MERGED} event.
     *                         This value together with the old value produced the new value.
     */
    void publishEvent(Address caller, String mapName, EntryEventType eventType,
                      Data dataKey, Object dataOldValue, Object dataValue, Object dataMergingValue);

    void publishMapPartitionLostEvent(Address caller, String mapName, int partitionId);

    /**
     * Only gives a hint which indicates that a map-wide operation has just been executed on this partition.
     * This method should not publish an event.
     * 
     * Currently a map event is published by the end which calls map#clear or map#evictAll and there is not
     * any order guarantee between events fired after map#put and map#clear, as a result of that, we may clear
     * a put after a map#clear, to tackle with that kind of possible anomalies, this hint may be used under
     * some conditions internally.
     */
    void hintMapEvent(Address caller, String mapName, EntryEventType eventType, int numberOfEntriesAffected, int partitionId);

    /**
     * Notifies {@link com.hazelcast.map.QueryCache} subscribers directly, without publishing an event to
     * other map listeners. This is necessary in certain cases, such as when loading entries into a map.
     *
     * @param eventData the event to publish to query caches
     */
    void addEventToQueryCache(Object eventData);

    /**
     * Returns {@code true} if there is at least one listener registered for the specified {@code mapName}.
     */
    boolean hasEventListener(String mapName);
}