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.service.accord.api;
  
  import java.util.List;
  import java.util.concurrent.RejectedExecutionException;
  import java.util.concurrent.ScheduledFuture;
  import java.util.concurrent.TimeUnit;
  
  import accord.api.Scheduler;
  import org.apache.cassandra.concurrent.ExecutorFactory;
  import org.apache.cassandra.concurrent.ScheduledExecutorPlus;
  import org.apache.cassandra.concurrent.Shutdownable;
  
  public class AccordScheduler implements Scheduler, Shutdownable
  {
      private final ScheduledExecutorPlus scheduledExecutor = ExecutorFactory.Global.executorFactory().scheduled(false, "AccordScheduled");
  
      private static class ScheduledFutureWrapper implements Scheduled
      {
          private final ScheduledFuture<?> future;
  
          public ScheduledFutureWrapper(ScheduledFuture<?> future)
          {
              this.future = future;
          }
  
          @Override
          public void cancel()
          {
              future.cancel(false);
          }
  
          @Override
          public boolean isDone()
          {
              return future.isDone();
          }
      }
  
      @Override
      public Scheduled recurring(Runnable run, long delay, TimeUnit units)
      {
          ScheduledFuture<?> future = scheduledExecutor.scheduleAtFixedRate(run, delay, delay, units);
          return new ScheduledFutureWrapper(future);
      }
  
      @Override
      public Scheduled once(Runnable run, long delay, TimeUnit units)
      {
          ScheduledFuture<?> future = scheduledExecutor.schedule(run, delay, units);
          return new ScheduledFutureWrapper(future);
      }
  
      @Override
      public Scheduled selfRecurring(Runnable run, long delay, TimeUnit units)
      {
          ScheduledFuture<?> future = scheduledExecutor.scheduleSelfRecurring(run, delay, units);
          return new ScheduledFutureWrapper(future);
      }
  
      @Override
      public void now(Runnable task)
      {
          // called from the mutation stage configured by the verb
          if (scheduledExecutor.isShutdown())
              throw new RejectedExecutionException("Scheduler has shut down.");
          scheduledExecutor.submit(task);
      }
  
      @Override
      public boolean isTerminated()
      {
          return scheduledExecutor.isTerminated();
      }
  
      @Override
      public void shutdown()
      {
          for (Runnable c : shutdownNow())
          {
              if (c instanceof java.util.concurrent.Future<?>)
                  ((java.util.concurrent.Future<?>) c).cancel(false);
          }
      }
  
      @Override
      public List<Runnable> shutdownNow()
      {
          return scheduledExecutor.shutdownNow();
      }
  
      @Override
      public boolean awaitTermination(long timeout, TimeUnit units) throws InterruptedException
      {
          return scheduledExecutor.awaitTermination(timeout, units);
      }
  }
  