1 /* 2 * Copyright 2017, OpenCensus Authors 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 17 package io.opencensus.implcore.common; 18 19 import io.opencensus.common.Clock; 20 import io.opencensus.common.Timestamp; 21 import javax.annotation.concurrent.ThreadSafe; 22 23 /** A {@link Clock} that uses {@link System#currentTimeMillis()} and {@link System#nanoTime()}. */ 24 @ThreadSafe 25 public final class MillisClock extends Clock { 26 private static final MillisClock INSTANCE = new MillisClock(); 27 MillisClock()28 private MillisClock() {} 29 30 /** 31 * Returns a {@code MillisClock}. 32 * 33 * @return a {@code MillisClock}. 34 */ getInstance()35 public static MillisClock getInstance() { 36 return INSTANCE; 37 } 38 39 @Override now()40 public Timestamp now() { 41 return Timestamp.fromMillis(System.currentTimeMillis()); 42 } 43 44 @Override nowNanos()45 public long nowNanos() { 46 return System.nanoTime(); 47 } 48 } 49