/*
 * Copyright 2016 Netflix, Inc.
 *
 * 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.rsocket.util;

import java.util.concurrent.TimeUnit;

/**
 * Abstraction to get current time and durations.
 */
public final class Clock {

    private Clock() {
        // No Instances.
    }

    public static long now() {
        return System.nanoTime() / 1000;
    }

    public static long elapsedSince(long timestamp) {
        long t = now();
        return Math.max(0L, t - timestamp);
    }

    public static TimeUnit unit() {
        return TimeUnit.MICROSECONDS;
    }
}
