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.util;
  
  import org.reactivestreams.*;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.disposables.Disposable;
  import io.reactivex.rxjava3.plugins.RxJavaPlugins;
  
  /**
   * Singleton implementing many interfaces as empty.
   */
  public enum EmptyComponent implements FlowableSubscriber<Object>, Observer<Object>, MaybeObserver<Object>,
  SingleObserver<Object>, CompletableObserver, Subscription, Disposable {
      INSTANCE;
  
      @SuppressWarnings("unchecked")
      public static <T> Subscriber<T> asSubscriber() {
          return (Subscriber<T>)INSTANCE;
      }
  
      @SuppressWarnings("unchecked")
      public static <T> Observer<T> asObserver() {
          return (Observer<T>)INSTANCE;
      }
  
      @Override
      public void dispose() {
          // deliberately no-op
      }
  
      @Override
      public boolean isDisposed() {
          return true;
      }
  
      @Override
      public void request(long n) {
          // deliberately no-op
      }
  
      @Override
      public void cancel() {
          // deliberately no-op
      }
  
      @Override
      public void onSubscribe(Disposable d) {
          d.dispose();
      }
  
      @Override
      public void onSubscribe(Subscription s) {
          s.cancel();
      }
  
      @Override
      public void onNext(Object t) {
          // deliberately no-op
      }
  
      @Override
      public void onError(Throwable t) {
          RxJavaPlugins.onError(t);
      }
  
      @Override
      public void onComplete() {
          // deliberately no-op
      }
  
      @Override
      public void onSuccess(Object value) {
          // deliberately no-op
      }
  }
  