| /** |
| * Licensed 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.aurora.common.util; |
| |
| import java.time.Instant; |
| |
| /** |
| * An abstraction of the system clock. |
| * @author John Sirois |
| */ |
| public interface Clock { |
| // TODO(zmanji): Consider replacing this with java.time.Clock |
| /** |
| * A clock that returns the the actual time reported by the system. |
| */ |
| Clock SYSTEM_CLOCK = new Clock() { |
| @Override public long nowMillis() { |
| return System.currentTimeMillis(); |
| } |
| @Override public long nowNanos() { |
| return System.nanoTime(); |
| } |
| @Override public void waitFor(long millis) throws InterruptedException { |
| Thread.sleep(millis); |
| } |
| @Override public Instant nowInstant() { |
| return Instant.now(); |
| } |
| }; |
| |
| /** |
| * Returns the current time in milliseconds since the epoch. |
| * |
| * @return The current time in milliseconds since the epoch. |
| * @see System#currentTimeMillis() |
| */ |
| long nowMillis(); |
| |
| /** |
| * Returns the current time in nanoseconds. Should be used only for relative timing. |
| * See {@code System.nanoTime()} for tips on using the value returned here. |
| * |
| * @return A measure of the current time in nanoseconds. |
| * @see System#nanoTime() |
| */ |
| long nowNanos(); |
| |
| /** |
| * Waits for the given amount of time to pass on this clock before returning. |
| * |
| * @param millis the amount of time to wait in milliseconds |
| * @throws InterruptedException if this wait was interrupted |
| */ |
| void waitFor(long millis) throws InterruptedException; |
| |
| /** |
| * Returns the current time as an java.time.Instant. |
| * |
| * @return the Instant representing the current time. |
| * @see Instant#now() |
| */ |
| Instant nowInstant(); |
| } |