1 /*

     2  * Copyright (c) 2007, 2017, 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 import java.io.File;

    25 import java.io.FileDescriptor;

    26 import java.io.FileOutputStream;

    27 import java.io.FileNotFoundException;

    28 import java.io.RandomAccessFile;

    29 import java.lang.ref.Cleaner;

    30 import java.lang.ref.Reference;

    31 import java.lang.ref.ReferenceQueue;

    32 import java.lang.ref.WeakReference;

    33 import java.lang.reflect.Field;

    34 import java.util.HashSet;

    35 

    36 /**

    37  * @test

    38  * @bug 8080225

    39  * @modules java.base/java.io:open

    40  * @summary Test to ensure that an unclosed and unreferenced RandomAccessFile closes the fd

    41  * @run main/othervm UnreferencedRAFClosesFd

    42  */

    43 public class UnreferencedRAFClosesFd {

    44 

    45     static final String FILE_NAME = "empty.txt";

    46 

    47     /* standalone interface */

    48     public static void main(String argv[]) throws Exception {

    49 

    50         File inFile= new File(System.getProperty("test.dir", "."), FILE_NAME);

    51         inFile.createNewFile();

    52         inFile.deleteOnExit();

    53 

    54         String name = inFile.getPath();

    55         RandomAccessFile raf;

    56         try {

    57             // raf is explicitly *not* closed to allow cleaner to work

    58             raf = new RandomAccessFile(name, "rw");

    59         } catch (FileNotFoundException e) {

    60             System.out.println("Unexpected exception " + e);

    61             throw(e);

    62         }

    63         FileDescriptor fd = raf.getFD();

    64 

    65         Field fdField = FileDescriptor.class.getDeclaredField("cleanup");

    66         fdField.setAccessible(true);

    67         Cleaner.Cleanable cleanup = (Cleaner.Cleanable)fdField.get(fd);

    68 

    69         // Prepare to wait for FOS, FD, Cleanup to be reclaimed

    70         ReferenceQueue<Object> queue = new ReferenceQueue<>();

    71         HashSet<Reference<?>> pending = new HashSet<>(3);

    72         pending.add(new WeakReference<>(cleanup, queue));

    73         pending.add(new WeakReference<>(raf, queue));

    74         pending.add(new WeakReference<>(fd, queue));

    75 

    76         Reference<?> r;

    77         while (((r = queue.remove(10L)) != null)

    78                 || !pending.isEmpty()) {

    79             System.out.printf("r: %s, pending: %d%n", r, pending.size());

    80             if (r != null) {

    81                 pending.remove(r);

    82             } else {

    83                 cleanup = null;

    84                 raf = null;

    85                 fd = null;

    86                 System.gc();  // attempt to reclaim the RAF, cleanup, and fd

    87             }

    88         }

    89 

    90         // Keep these variables in scope as gc roots

    91         Reference.reachabilityFence(cleanup);

    92         Reference.reachabilityFence(fd);

    93         Reference.reachabilityFence(raf);

    94         Reference.reachabilityFence(pending);

    95     }

    96 }