content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.apache.cassandra.utils;
  
  import java.util.concurrent.TimeUnit;
  
  /**
   * A freely adjustable clock that can be used for unit testing. See {@link MonotonicClock#instance} how to
   * enable this class.
   */
  public class FreeRunningClock implements MonotonicClock
  {
      private long nanoTime;
      private long millisSinceEpoch;
      private long error;
  
      public FreeRunningClock()
      {
          this.nanoTime = 0;
      }
  
      public FreeRunningClock(long nanoTime)
      {
          this.nanoTime = nanoTime;
      }
  
      public FreeRunningClock(long nanoTime, long millisSinceEpoch, long error)
      {
          this.nanoTime = nanoTime;
          this.millisSinceEpoch = millisSinceEpoch;
          this.error = error;
      }
  
      @Override
      public long now()
      {
          return nanoTime;
      }
  
      @Override
      public long error()
      {
          return error;
      }
  
      @Override
      public MonotonicClockTranslation translate()
      {
          return new AbstractEpochSamplingClock.AlmostSameTime(millisSinceEpoch, nanoTime, error);
      }
  
      @Override
      public boolean isAfter(long instant)
      {
          return instant > nanoTime;
      }
  
      @Override
      public boolean isAfter(long now, long instant)
      {
          return now > instant;
      }
  
      public void advance(long time, TimeUnit unit)
      {
          nanoTime += unit.toNanos(time);
      }
  }
  