1 /*
   2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  */
  22 
  23 /*
  24  * This file is available under and governed by the GNU General Public
  25  * License version 2 only, as published by the Free Software Foundation.
  26  * However, the following notice accompanied the original version of this
  27  * file:
  28  *
  29  * Written by Doug Lea with assistance from members of JCP JSR-166
  30  * Expert Group and released to the public domain, as explained at
  31  * http://creativecommons.org/licenses/publicdomain
  32  */
  33 
  34 import java.util.*;
  35 import java.util.concurrent.*;
  36 
  37 /*
  38  * @test
  39  * @bug 6805775 6815766
  40  * @summary Check weak consistency of concurrent queue iterators
  41  */
  42 
  43 @SuppressWarnings({"unchecked", "rawtypes"})
  44 public class IteratorWeakConsistency {
  45 
  46     void test(String[] args) throws Throwable {
  47         test(new LinkedBlockingQueue());
  48         test(new LinkedBlockingQueue(20));
  49         test(new LinkedBlockingDeque());
  50         test(new LinkedBlockingDeque(20));
  51         test(new ConcurrentLinkedDeque());
  52         test(new ConcurrentLinkedQueue());
  53         test(new LinkedTransferQueue());
  54         // Other concurrent queues (e.g. ArrayBlockingQueue) do not
  55         // currently have weakly consistent iterators.
  56         // test(new ArrayBlockingQueue(20));
  57     }
  58 
  59     void test(Queue q) throws Throwable {
  60         // TODO: make this more general
  61         for (int i = 0; i < 10; i++)
  62             q.add(i);
  63         Iterator it = q.iterator();
  64         q.poll();
  65         q.poll();
  66         q.poll();
  67         q.remove(7);
  68         List list = new ArrayList();
  69         while (it.hasNext())
  70             list.add(it.next());
  71         equal(list, Arrays.asList(0, 3, 4, 5, 6, 8, 9));
  72         check(! list.contains(null));
  73         System.out.printf("%s: %s%n",
  74                           q.getClass().getSimpleName(),
  75                           list);
  76     }
  77 
  78     //--------------------- Infrastructure ---------------------------
  79     volatile int passed = 0, failed = 0;
  80     void pass() {passed++;}
  81     void fail() {failed++; Thread.dumpStack();}
  82     void fail(String msg) {System.err.println(msg); fail();}
  83     void unexpected(Throwable t) {failed++; t.printStackTrace();}
  84     void check(boolean cond) {if (cond) pass(); else fail();}
  85     void equal(Object x, Object y) {
  86         if (x == null ? y == null : x.equals(y)) pass();
  87         else fail(x + " not equal to " + y);}
  88     static Class<?> thisClass = new Object(){}.getClass().getEnclosingClass();
  89     public static void main(String[] args) throws Throwable {
  90         new IteratorWeakConsistency().instanceMain(args);}
  91     public void instanceMain(String[] args) throws Throwable {
  92         try {test(args);} catch (Throwable t) {unexpected(t);}
  93         System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
  94         if (failed > 0) throw new AssertionError("Some tests failed");}
  95 }