Madan Jampani | 0583387 | 2016-07-12 23:01:39 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2016-present Open Networking Laboratory |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.onosproject.core; |
| 17 | |
| 18 | import org.onosproject.store.service.WallClockTimestamp; |
| 19 | |
| 20 | /** |
| 21 | * The <a href="http://www.cse.buffalo.edu/tech-reports/2014-04.pdf">hybrid logical time</a> keeper service. |
| 22 | */ |
| 23 | public interface HybridLogicalClockService { |
| 24 | |
| 25 | /** |
| 26 | * Returns the current hybrid logical time. |
| 27 | * @return current hybrid logical time |
| 28 | */ |
| 29 | HybridLogicalTime timeNow(); |
| 30 | |
| 31 | /** |
| 32 | * Records a (receive) event and accordingly makes adjustments to the hybrid logical time. |
| 33 | * @param time received event time |
| 34 | */ |
| 35 | void recordEventTime(HybridLogicalTime time); |
| 36 | |
| 37 | /** |
| 38 | * Returns the current time derived from the hybrid logical time. |
| 39 | * @return current system time |
| 40 | */ |
| 41 | default long now() { |
| 42 | return timeNow().time(); |
| 43 | } |
| 44 | |
| 45 | /** |
| 46 | * Returns the current time as a {@code WallClockTimestamp}. |
| 47 | * @return wall clock timestamp |
| 48 | */ |
| 49 | default WallClockTimestamp wallClockTimestamp() { |
| 50 | return new WallClockTimestamp(now()); |
| 51 | } |
| 52 | } |