code: /*
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * 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.reactivex.rxjava3.internal.operators.completable;
  
  import java.util.concurrent.atomic.AtomicInteger;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.disposables.Disposable;
  import io.reactivex.rxjava3.exceptions.Exceptions;
  import io.reactivex.rxjava3.functions.Action;
  import io.reactivex.rxjava3.internal.disposables.DisposableHelper;
  import io.reactivex.rxjava3.plugins.RxJavaPlugins;
  
  /**
   * Execute an action after an onError, onComplete or a dispose event.
   * <p>History: 2.0.1 - experimental
   * @since 2.1
   */
  public final class CompletableDoFinally extends Completable {
  
      final CompletableSource source;
  
      final Action onFinally;
  
      public CompletableDoFinally(CompletableSource source, Action onFinally) {
          this.source = source;
          this.onFinally = onFinally;
      }
  
      @Override
      protected void subscribeActual(CompletableObserver observer) {
          source.subscribe(new DoFinallyObserver(observer, onFinally));
      }
  
      static final class DoFinallyObserver extends AtomicInteger implements CompletableObserver, Disposable {
  
          private static final long serialVersionUID = 4109457741734051389L;
  
          final CompletableObserver downstream;
  
          final Action onFinally;
  
          Disposable upstream;
  
          DoFinallyObserver(CompletableObserver actual, Action onFinally) {
              this.downstream = actual;
              this.onFinally = onFinally;
          }
  
          @Override
          public void onSubscribe(Disposable d) {
              if (DisposableHelper.validate(this.upstream, d)) {
                  this.upstream = d;
  
                  downstream.onSubscribe(this);
              }
          }
  
          @Override
          public void onError(Throwable t) {
              downstream.onError(t);
              runFinally();
          }
  
          @Override
          public void onComplete() {
              downstream.onComplete();
              runFinally();
          }
  
          @Override
          public void dispose() {
              upstream.dispose();
              runFinally();
          }
  
          @Override
          public boolean isDisposed() {
              return upstream.isDisposed();
          }
  
          void runFinally() {
              if (compareAndSet(0, 1)) {
                  try {
                      onFinally.run();
                  } catch (Throwable ex) {
                      Exceptions.throwIfFatal(ex);
                      RxJavaPlugins.onError(ex);
                  }
              }
          }
      }
  }
  