/**
* Copyright 2014 Netflix, Inc.
* <p/>
* 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
* <p/>
* http://www.apache.org/licenses/LICENSE-2.0
* <p/>
* 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 com.netflix.servo.util;
/**
* A wrapper around the system clock to allow custom implementations to be used in unit tests
* where we want to fake or control the clock behavior.
*/
public interface Clock {
/**
* A Clock instance that returns the current time in milliseconds since
* the epoch using the system clock.
*/
Clock WALL = System::currentTimeMillis;
/**
* Returns the number of milliseconds since the epoch.
*/
long now();
}