1 /* 2 * Copyright (c) 2015, 2018, 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.internal.net.http; 27 28 import java.time.Duration; 29 import java.time.Instant; 30 import java.util.concurrent.atomic.AtomicLong; 31 32 /** 33 * Timeout event notified by selector thread. Executes the given handler if 34 * the timer not canceled first. 35 * 36 * Register with {@link HttpClientImpl#registerTimer(TimeoutEvent)}. 37 * 38 * Cancel with {@link HttpClientImpl#cancelTimer(TimeoutEvent)}. 39 */ 40 abstract class TimeoutEvent implements Comparable<TimeoutEvent> { 41 42 private static final AtomicLong COUNTER = new AtomicLong(); 43 // we use id in compareTo to make compareTo consistent with equals 44 // see TimeoutEvent::compareTo below; 45 private final long id = COUNTER.incrementAndGet(); 46 private final Instant deadline; 47 48 TimeoutEvent(Duration duration) { 49 deadline = Instant.now().plus(duration); 50 } 51 52 public abstract void handle(); 53 54 public Instant deadline() { 55 return deadline; 56 } 57 58 @Override 59 public int compareTo(TimeoutEvent other) { 60 if (other == this) return 0; 61 // if two events have the same deadline, but are not equals, then the 62 // smaller is the one that was created before (has the smaller id). 63 // This is arbitrary and we don't really care which is smaller or 64 // greater, but we need a total order, so two events with the 65 // same deadline cannot compare == 0 if they are not equals. 66 final int compareDeadline = this.deadline.compareTo(other.deadline); 67 if (compareDeadline == 0 && !this.equals(other)) { 68 long diff = this.id - other.id; // should take care of wrap around 69 if (diff < 0) return -1; 70 else if (diff > 0) return 1; 71 else assert false : "Different events with same id and deadline"; 72 } 73 return compareDeadline; 74 } 75 76 @Override 77 public String toString() { 78 return "TimeoutEvent[id=" + id + ", deadline=" + deadline + "]"; 79 } 80 }