/** * 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.internal.util; import org.reactivestreams.*; import io.reactivex.*; import io.reactivex.disposables.Disposable; import io.reactivex.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 } }