karanmehta93 commented on a change in pull request #425: PHOENIX-5069 Use asynchronous refresh to provide non-blocking Phoenix Stats Client Cache URL: https://github.com/apache/phoenix/pull/425#discussion_r249196289
########## File path: phoenix-core/src/main/java/org/apache/phoenix/query/PhoenixStatsLoader.java ########## @@ -0,0 +1,57 @@ +/* + * 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. + */ +package org.apache.phoenix.query; + +import org.apache.phoenix.schema.stats.GuidePostsInfo; +import org.apache.phoenix.schema.stats.GuidePostsKey; + +/** + * The interface for talking to underneath layers to load stats from stats table for a given key + */ +public interface PhoenixStatsLoader { + /** + * Use to check whether this is the time to load stats from stats table. + * There are two cases: + * a. After a specified duration has passed + * b. The stats on server side (e.g. in stats table) has been updated + * + * @return boolean indicates whether we need to load stats or not + */ + boolean needsLoad(); + + /** + * Called by client stats cache to load stats from underneath layers + * + * @param statsKey the stats key used to search the stats on server side (in stats table) + * @throws Exception + * + * @return GuidePostsInfo retrieved from sever side + */ + GuidePostsInfo loadStats(GuidePostsKey statsKey) throws Exception; Review comment: Do we really want two separate methods for this? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on 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
