1 /*
   2  * Copyright (c) 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.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /* @test
  25  * @bug 8201315
  26  * @summary Test that channels can be registered, interest ops can changed,
  27  *          and keys cancelled while a selection operation is in progress.
  28  */
  29 
  30 import java.io.IOException;

  31 import java.nio.channels.Pipe;
  32 import java.nio.channels.SelectionKey;
  33 import java.nio.channels.Selector;
  34 import java.util.concurrent.Callable;
  35 import java.util.concurrent.ExecutorService;
  36 import java.util.concurrent.Executors;
  37 import java.util.concurrent.Future;
  38 import java.util.concurrent.Phaser;
  39 
  40 public class RegisterDuringSelect {
  41 
  42     static Callable<Void> selectLoop(Selector sel, Phaser barrier) {
  43         return new Callable<Void>() {
  44             @Override
  45             public Void call() throws IOException {
  46                 for (;;) {

  47                     sel.select();



  48                     if (sel.isOpen()) {
  49                         barrier.arriveAndAwaitAdvance();

  50                     } else {
  51                         // closed
  52                         return null;
  53                     }
  54                 }
  55             }
  56         };
  57     }
  58     /**
  59      * Invoke register, interestOps, and cancel concurrently with a thread
  60      * doing a selection operation
  61      */
  62     public static void main(String args[]) throws Exception {
  63         Future<Void> result;
  64 
  65         ExecutorService pool = Executors.newFixedThreadPool(1);
  66         try (Selector sel = Selector.open()) {
  67             Phaser barrier = new Phaser(2);
  68 
  69             // submit task to do the select loop
  70             result = pool.submit(selectLoop(sel, barrier));
  71 
  72             Pipe p = Pipe.open();
  73             try {
  74                 Pipe.SourceChannel sc = p.source();
  75                 sc.configureBlocking(false);
  76 
  77                 System.out.println("register ...");
  78                 SelectionKey key = sc.register(sel, SelectionKey.OP_READ);
  79                 if (!sel.keys().contains(key))
  80                     throw new RuntimeException("key not in key set");
  81                 sel.wakeup();
  82                 barrier.arriveAndAwaitAdvance();
  83 
  84                 System.out.println("interestOps ...");
  85                 key.interestOps(0);
  86                 sel.wakeup();
  87                 barrier.arriveAndAwaitAdvance();
  88 
  89                 System.out.println("cancel ...");
  90                 key.cancel();
  91                 sel.wakeup();
  92                 barrier.arriveAndAwaitAdvance();
  93                 if (sel.keys().contains(key))
  94                     throw new RuntimeException("key not removed from key set");
  95 
  96             } finally {
  97                 p.source().close();
  98                 p.sink().close();
  99             }
 100 
 101         } finally {
 102             pool.shutdown();
 103         }
 104 
 105         // ensure selectLoop completes without exception
 106         result.get();
 107 
 108     }
 109 }
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