hazelcast-master/hazelcast/src/main/java/com/hazelcast/internal/services/PostJoinAwareService.java
/*
 * Copyright (c) 2008-2023, 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.services;

import com.hazelcast.spi.impl.operationservice.Operation;
import com.hazelcast.spi.impl.operationservice.PartitionAwareOperation;

/**
 * Marker interface for services that want to return operations to be executed on the cluster
 * members after a join has been finalized.
 */
public interface PostJoinAwareService {

    /**
     * Post join operations must be lock free, meaning no locks at all:
     * no partition locks, no key-based locks, no service level locks, no database interaction!
     * The {@link Operation#getPartitionId()} method should return a negative value.
     * This means that the operations should not implement {@link PartitionAwareOperation}.
     * <p>
     * Post join operations should return response, at least a {@code null} response.
     *
     * @return a response from the post join operation. Can be {@code null}.
     */
    Operation getPostJoinOperation();

}
