1 /* 2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.incubator.http; 27 28 import java.util.concurrent.Flow; 29 import java.util.concurrent.atomic.AtomicBoolean; 30 31 // Completes the subscription on first request. Never calls onNext() 32 33 class PseudoPublisher<T> implements Flow.Publisher<T> { 34 35 private final Throwable throwable; 36 37 PseudoPublisher() { 38 this(null); 39 } 40 41 PseudoPublisher(Throwable throwable) { 42 this.throwable = throwable; 43 } 44 45 @Override 46 public void subscribe(Flow.Subscriber<? super T> subscriber) { 47 subscriber.onSubscribe(new Subscription(subscriber)); 48 } 49 50 private class Subscription implements Flow.Subscription { 51 52 private final Flow.Subscriber<? super T> subscriber; 53 private final AtomicBoolean done = new AtomicBoolean(); 54 55 Subscription(Flow.Subscriber<? super T> subscriber) { 56 this.subscriber = subscriber; 57 } 58 59 @Override 60 public void request(long n) { 61 if (done.compareAndSet(false, true)) { 62 if (n > 0) { 63 if (throwable == null) { 64 subscriber.onComplete(); 65 } else { 66 subscriber.onError(throwable); 67 } 68 } else { 69 subscriber.onError(new IllegalArgumentException("request(" + n + ")")); 70 } 71 } 72 } 73 74 @Override 75 public void cancel() { 76 done.set(true); 77 } 78 79 } 80 }