1 /*
   2  * Copyright (c) 2007, 2008, 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 /*
  25  * @test
  26  * @bug 6631352
  27  * @summary Check that appends are atomic
  28  */
  29 
  30 import java.io.File;
  31 import java.io.FileOutputStream;
  32 import java.util.concurrent.Executors;
  33 import java.util.concurrent.ExecutorService;
  34 import java.util.concurrent.TimeUnit;
  35 
  36 public class AtomicAppend {
  37     // Before the fix for
  38     // 6631352: Implement atomic append mode using FILE_APPEND_DATA (win)
  39     // this would fail intermittently on windows
  40     void test(String[] args) throws Throwable {
  41         final int nThreads = 10;
  42         final int writes = 1000;
  43         final File file = new File("foo");
  44         file.delete();
  45         try {
  46             final ExecutorService es = Executors.newFixedThreadPool(nThreads);
  47             for (int i = 0; i < nThreads; i++)
  48                 es.execute(new Runnable() { public void run() {
  49                     try {
  50                         try (FileOutputStream s = new FileOutputStream(file, true)) {
  51                             for (int j = 0; j < 1000; j++) {
  52                                 s.write((int) 'x');
  53                                 s.flush();
  54                             }
  55                         }
  56                     } catch (Throwable t) { unexpected(t); }}});
  57             es.shutdown();
  58             es.awaitTermination(10L, TimeUnit.MINUTES);
  59             equal(file.length(), (long) (nThreads * writes));
  60         } finally {
  61             file.delete();
  62         }
  63     }
  64 
  65     //--------------------- Infrastructure ---------------------------
  66     volatile int passed = 0, failed = 0;
  67     void pass() {passed++;}
  68     void fail() {failed++; Thread.dumpStack();}
  69     void fail(String msg) {System.err.println(msg); fail();}
  70     void unexpected(Throwable t) {failed++; t.printStackTrace();}
  71     void check(boolean cond) {if (cond) pass(); else fail();}
  72     void equal(Object x, Object y) {
  73         if (x == null ? y == null : x.equals(y)) pass();
  74         else fail(x + " not equal to " + y);}
  75     public static void main(String[] args) throws Throwable {
  76         new AtomicAppend().instanceMain(args);}
  77     void instanceMain(String[] args) throws Throwable {
  78         try {test(args);} catch (Throwable t) {unexpected(t);}
  79         System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
  80         if (failed > 0) throw new AssertionError("Some tests failed");}
  81 }