jiajunwang commented on a change in pull request #827: Add intermediate storage for customized state URL: https://github.com/apache/helix/pull/827#discussion_r388112109
########## File path: helix-core/src/main/java/org/apache/helix/common/caches/ParticipantStateCache.java ########## @@ -0,0 +1,177 @@ +package org.apache.helix.common.caches; + +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF 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. + */ + +import com.google.common.collect.Maps; +import java.util.ArrayList; +import java.util.Collections; +import java.util.HashMap; +import java.util.HashSet; +import java.util.List; +import java.util.Map; +import java.util.Set; +import org.apache.helix.HelixDataAccessor; +import org.apache.helix.PropertyKey; +import org.apache.helix.common.controllers.ControlContextProvider; +import org.apache.helix.controller.LogUtil; +import org.apache.helix.model.LiveInstance; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +/** + * Represent a cache that holds a certain participant side state of for the whole cluster. + */ +public abstract class ParticipantStateCache<T> extends AbstractDataCache { + private static Logger LOG = LoggerFactory.getLogger(ParticipantStateCache.class); + protected Map<String, Map<String, Map<String, T>>> _participantStateMap; + + protected Map<PropertyKey, T> _participantStateCache = Maps.newHashMap(); + + public ParticipantStateCache(ControlContextProvider controlContextProvider) { + super(controlContextProvider); + _participantStateMap = new HashMap<>(); + } + + /** + * This refreshes the participant state cache data by re-fetching the data from zookeeper in an + * efficient way + * @param accessor + * @param liveInstanceMap map of all liveInstances in cluster + * @return + */ + public boolean refresh(HelixDataAccessor accessor, Map<String, LiveInstance> liveInstanceMap, + Boolean snapshotEnabled) { Review comment: Should this boolean be fixed once the class is coded? Overall, I don't think we need it. Just call refreshSnapshot() anyway. If there is no such implementation, the child class won't implement it anyway. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
