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.concurrent;
  
  import java.util.List;
  import java.util.concurrent.Callable;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.TimeUnit;
  
  import com.google.common.util.concurrent.FutureCallback;
  import com.google.common.util.concurrent.Futures;
  import com.google.common.util.concurrent.ListenableFuture;
  import com.google.common.util.concurrent.MoreExecutors;
  
  import org.apache.cassandra.utils.WithResources;
  import org.apache.cassandra.utils.concurrent.AsyncPromise;
  import org.apache.cassandra.utils.concurrent.Future;
  
  public class ForwardingExecutorPlus implements ExecutorPlus, SequentialExecutorPlus, LocalAwareExecutorPlus
  {
      private final ExecutorService delegate;
  
      public ForwardingExecutorPlus(ExecutorService delegate)
      {
          this.delegate = delegate;
      }
  
      protected ExecutorService delegate()
      {
          return delegate;
      }
  
      @Override
      public void shutdown()
      {
          delegate().shutdown();
      }
  
      @Override
      public List<Runnable> shutdownNow()
      {
          return delegate().shutdownNow();
      }
  
      @Override
      public boolean isShutdown()
      {
          return delegate().isShutdown();
      }
  
      @Override
      public boolean isTerminated()
      {
          return delegate().isTerminated();
      }
  
      @Override
      public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException
      {
          return delegate().awaitTermination(timeout, unit);
      }
  
      @Override
      public <T> Future<T> submit(Callable<T> task)
      {
          return wrap(delegate().submit(task));
      }
  
      @Override
      public <T> Future<T> submit(Runnable task, T result)
      {
          return wrap(delegate().submit(task, result));
      }
  
      @Override
      public Future<?> submit(Runnable task)
      {
          return wrap(delegate().submit(task));
      }
  
      @Override
      public void execute(WithResources withResources, Runnable task)
      {
          execute(TaskFactory.standard().toExecute(withResources, task));
      }
  
      @Override
      public <T> Future<T> submit(WithResources withResources, Callable<T> task)
      {
          class Catch
          {
              T value;
          }
          Catch c = new Catch();
          Runnable exec = TaskFactory.standard().toExecute(withResources, () -> {
              try
              {
                  c.value = task.call();
              }
              catch (Exception e)
              {
                  throw new RuntimeException(e);
              }
          });
          return submit(() -> {
              exec.run();
              return c.value;
          });
      }
  
      @Override
      public Future<?> submit(WithResources withResources, Runnable task)
      {
          return submit(TaskFactory.standard().toExecute(withResources, task));
      }
  
      @Override
      public <T> Future<T> submit(WithResources withResources, Runnable task, T result)
      {
          return submit(Executors.callable(TaskFactory.standard().toSubmit(withResources, task), result));
      }
  
      @Override
      public boolean inExecutor()
      {
          return false;
      }
  
      @Override
      public void execute(Runnable command)
      {
          delegate().execute(command);
      }
  
      @Override
      public int getCorePoolSize()
      {
          return 0;
      }
  
      @Override
      public void setCorePoolSize(int newCorePoolSize)
      {
  
      }
  
      @Override
      public int getMaximumPoolSize()
      {
          return 0;
      }
  
      @Override
      public void setMaximumPoolSize(int newMaximumPoolSize)
      {
  
      }
  
      @Override
      public int getActiveTaskCount()
      {
          return 0;
      }
  
      @Override
      public long getCompletedTaskCount()
      {
          return 0;
      }
  
      @Override
      public int getPendingTaskCount()
      {
          return 0;
      }
  
      private <T> Future<T> wrap(java.util.concurrent.Future<T> submit)
      {
          if (submit instanceof Future)
              return (Future<T>) submit;
          if (submit instanceof ListenableFuture)
          {
              AsyncPromise<T> promise = new AsyncPromise<>();
              Futures.addCallback((ListenableFuture<T>) submit, new FutureCallback<T>()
              {
                  @Override
                  public void onSuccess(T result)
                  {
                      promise.setSuccess(result);
                  }
  
                  @Override
                  public void onFailure(Throwable t)
                  {
                      promise.setFailure(t);
                  }
              }, MoreExecutors.directExecutor());
              return promise;
          }
          throw new IllegalStateException("Unexpected future type: " + submit.getClass());
      }
  
      @Override
      public AtLeastOnceTrigger atLeastOnceTrigger(Runnable runnable)
      {
          return new SingleThreadExecutorPlus.AtLeastOnce(this, runnable);
      }
  }
  