| /* |
| * Copyright 2017, OpenCensus Authors |
| * |
| * 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 io.opencensus.implcore.internal; |
| |
| import io.opencensus.common.Clock; |
| import io.opencensus.common.Timestamp; |
| import javax.annotation.concurrent.Immutable; |
| |
| /** |
| * This class provides a mechanism for converting {@link System#nanoTime() nanoTime} values to |
| * {@link Timestamp}. |
| */ |
| @Immutable |
| public final class TimestampConverter { |
| private final Timestamp timestamp; |
| private final long nanoTime; |
| |
| // Returns a WallTimeConverter initialized to now. |
| public static TimestampConverter now(Clock clock) { |
| return new TimestampConverter(clock.now(), clock.nowNanos()); |
| } |
| |
| /** |
| * Converts a {@link System#nanoTime() nanoTime} value to {@link Timestamp}. |
| * |
| * @param nanoTime value to convert. |
| * @return the {@code Timestamp} representation of the {@code time}. |
| */ |
| public Timestamp convertNanoTime(long nanoTime) { |
| return timestamp.addNanos(nanoTime - this.nanoTime); |
| } |
| |
| private TimestampConverter(Timestamp timestamp, long nanoTime) { |
| this.timestamp = timestamp; |
| this.nanoTime = nanoTime; |
| } |
| } |