sanpwc commented on code in PR #896: URL: https://github.com/apache/ignite-3/pull/896#discussion_r907545447
########## modules/core/src/main/java/org/apache/ignite/hlc/HybridClock.java: ########## @@ -0,0 +1,75 @@ +/* + * 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.ignite.hlc; + +import java.time.Clock; +import org.apache.ignite.internal.tostring.S; + +/** + * A Hybrid Logical Clock. + */ +public class HybridClock { + /** Latest timestamp. */ + private HybridTimestamp latestTime; + + /** + * The constructor which initializes the latest time to current time by system clock. + */ + public HybridClock() { + this.latestTime = new HybridTimestamp(Clock.systemUTC().instant().toEpochMilli(), 0); + } + + /** + * Creates a timestamp for new event. + * + * @return The hybrid timestamp. + */ + public synchronized HybridTimestamp now() { + long currentTimeMillis = Clock.systemUTC().instant().toEpochMilli(); + + if (latestTime.getPhysical() >= currentTimeMillis) { + latestTime = latestTime.addTicks(1); + } else { + latestTime = new HybridTimestamp(currentTimeMillis, 0); + } + + return latestTime; + } + + /** + * Creates a timestamp for a received event. + * + * @param requestTime Timestamp from request. + * @return The hybrid timestamp. + */ + public synchronized HybridTimestamp tick(HybridTimestamp requestTime) { + HybridTimestamp now = new HybridTimestamp(Clock.systemUTC().instant().toEpochMilli(), -1); Review Comment: Do we really need to create HybridTimestamp instance in order to only compare it's physical? I believe should postpone new gerHybridTIme instantiation and do it only if now.physical is bigger than request.physical and latestTime.physical. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
