com.hazelcast.internal.crdt.CRDTReplicationAwareService Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2020, 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.crdt;
import com.hazelcast.cluster.impl.VectorClock;
import java.util.Map;
/**
* Represents a service implementing a CRDT that may be replicated and
* migrated to other replicas of the same CRDT. The service may optimize the
* replication operation contents depending on the provided vector clocks.
* The vector clock map contains mappings from CRDT name to the last
* successfully replicated CRDT state version. All CRDTs in this map should
* be of the same type.
*
* @param CRDT implementation type
*/
public interface CRDTReplicationAwareService {
/**
* Returns a replication operation for the provided vector clocks.
* The vector clock map contains mappings from CRDT name to the last
* successfully replicated CRDT vector clock. All CRDTs in this map should
* be of the same type.
* A return value of {@code null} means that there should not be any
* replication operation.
*
* @param lastReplicatedVectorClock last successfully replicated vector clock
* @param targetIndex the index of the replication target in
* the membership list containing only data members
* @return the replication operation and the replicated vector clocks
*/
CRDTReplicationContainer prepareReplicationOperation(Map lastReplicatedVectorClock, int targetIndex);
/** Returns the name of the service */
String getName();
/**
* Performs a merge of the local {@code name} CRDT with the provided state.
*
* @param name the CRDT name
* @param value the CRDT state to merge into the local state
*/
void merge(String name, T value);
/**
* Returns a migration operation for all of the CRDT states not owned by
* this member.
*
* @param maxConfiguredReplicaCount the maximum configured replica count
* for the CRDTs to be migrated (excluding)
* @return the migration operation and the current vector clocks
*/
CRDTReplicationContainer prepareMigrationOperation(int maxConfiguredReplicaCount);
/**
* Removes all of the CRDTs with vector clocks equal to the provided vector
* clocks.
* The vector clock map contains mappings from CRDT name to a vector clock.
* All CRDTs in this map should be of the same type.
*
* @param vectorClocks a map from CRDT name to a vector clock
* @return {@code true} if all of the CRDT states have been cleared,
* {@code false} otherwise
*/
boolean clearCRDTState(Map vectorClocks);
/**
* Prepares the service for replication and shutdown. After this method has
* returned, no mutations must be allowed to any existing CRDT state in
* this service and new CRDT states must be disallowed.
*/
void prepareToSafeShutdown();
}