/*
 * Copyright (C) 2011 The Guava 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 org.glassfish.jersey.internal.guava;

A time source; returns a time value representing the number of nanoseconds elapsed since some fixed but arbitrary point in time. Note that most users should use Stopwatch instead of interacting with this class directly. 

Warning: this interface can only be used to measure elapsed time, not wall time.
Author:
Kevin Bourrillion
Since:
10.0
(mostly source-compatible since 9.0)/**
 * A time source; returns a time value representing the number of nanoseconds elapsed since some
 * fixed but arbitrary point in time. Note that most users should use {@link Stopwatch} instead of
 * interacting with this class directly.
 * <p>
 * <p><b>Warning:</b> this interface can only be used to measure elapsed time, not wall time.
 *
 * @author Kevin Bourrillion
 * @since 10.0
 * (<a href="http://code.google.com/p/guava-libraries/wiki/Compatibility"
 * >mostly source-compatible</a> since 9.0)
 */
public abstract class Ticker {
    private static final Ticker SYSTEM_TICKER = new Ticker() {
        @Override
        public long read() {
            return Platform.systemNanoTime();
        }
    };

    
Constructor for use by subclasses.
/**
     * Constructor for use by subclasses.
     */
    Ticker() {
    }

    
A ticker that reads the current time using System.nanoTime. 
Since:
10.0/**
     * A ticker that reads the current time using {@link System#nanoTime}.
     *
     * @since 10.0
     */
    public static Ticker systemTicker() {
        return SYSTEM_TICKER;
    }

    
Returns the number of nanoseconds elapsed since this ticker's fixed
point of reference.
/**
     * Returns the number of nanoseconds elapsed since this ticker's fixed
     * point of reference.
     */
    public abstract long read();
}