1 /*

     2  * Copyright (c) 2007, 2011, 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 }