content: /*
   * 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.airlift.testing;
  
  import java.time.Clock;
  import java.time.Instant;
  import java.time.ZoneId;
  import java.time.ZoneOffset;
  import java.util.concurrent.TimeUnit;
  
  import static com.google.common.base.Preconditions.checkArgument;
  import static java.util.Objects.requireNonNull;
  
  public final class TestingClock
          extends Clock
  {
      private final ZoneId zone;
      private Instant instant;
  
      public TestingClock()
      {
          this(ZoneOffset.UTC);
      }
  
      public TestingClock(ZoneId zone)
      {
          this(zone, Instant.ofEpochMilli(1575000618963L));
      }
  
      private TestingClock(ZoneId zone, Instant instant)
      {
          this.zone = requireNonNull(zone, "zone is null");
          this.instant = requireNonNull(instant, "instant is null");
      }
  
      @Override
      public ZoneId getZone()
      {
          return zone;
      }
  
      @Override
      public Clock withZone(ZoneId zone)
      {
          return new TestingClock(zone, instant);
      }
  
      @Override
      public Instant instant()
      {
          return instant;
      }
  
      public void increment(long delta, TimeUnit unit)
      {
          checkArgument(delta >= 0, "delta is negative");
          instant = instant.plusNanos(unit.toNanos(delta));
      }
  }
  