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/*
* Copyright 2020 The Hekate Project
*
* The Hekate Project licenses this file to you 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 io.hekate.core.service;
import io.hekate.core.Hekate;
/**
* Lifecycle interface for services that depend on some other services.
*
*
* {@link Service}s can implement this interface in order to obtain references to some other services that they depend on. The {@link
* #resolve(DependencyContext)} method of this interface gets called only once by a {@link Hekate} instance right after the service
* gets {@link ServiceFactory#createService() constructed} and never gets called again even if node leaves and then rejoins the cluster.
*
*
*
* The order of dependencies resolution also influences on the services {@link InitializingService initialization} and {@link
* TerminatingService termination} order. If service {@code A} depends on services {@code B} and {@code C} then it is guaranteed that
* services {@code B} and {@code C} will be {@link InitializingService initialized} before the service {@code A} and will be {@link
* TerminatingService terminated} after the service {@code A}.
*
*
* @see InitializingService
* @see TerminatingService
*/
public interface DependentService {
/**
* Resolves dependencies of this service.
*
* @param ctx Dependency resolution context.
*/
void resolve(DependencyContext ctx);
}