| /* |
| * Copyright (c) 2013, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* @test |
| * @bug 8024833 |
| * @key intermittent |
| * @summary Tests interruption of threads mapping sections of a file channel in |
| * an attempt to deadlock due to nesting of begin calls. |
| */ |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.nio.channels.*; |
| import java.nio.channels.FileChannel.MapMode; |
| import java.nio.file.*; |
| import java.util.concurrent.Semaphore; |
| import static java.nio.file.StandardOpenOption.*; |
| |
| public class InterruptMapDeadlock { |
| |
| static class Mapper extends Thread { |
| final FileChannel fc; |
| final Semaphore gate; |
| volatile Exception exception; |
| |
| Mapper(FileChannel fc, Semaphore gate) { |
| this.fc = fc; |
| this.gate = gate; |
| } |
| |
| @Override |
| public void run() { |
| try { |
| gate.acquireUninterruptibly(); |
| fc.map(MapMode.READ_ONLY, 0, 1); |
| throw new Exception("Map succeeded"); |
| } catch (IOException x) { |
| System.out.println(x.getClass() + " (expected)"); |
| } catch (Exception unexpected) { |
| this.exception = unexpected; |
| } |
| } |
| |
| Exception exception() { |
| return exception; |
| } |
| |
| static Mapper startMapper(FileChannel fc, Semaphore gate) { |
| Mapper r = new Mapper(fc, gate); |
| r.setDaemon(true); |
| r.start(); |
| return r; |
| } |
| } |
| |
| static class Interruptor extends Thread { |
| |
| final Mapper[] mappers; |
| final Semaphore gate; |
| |
| Interruptor(Mapper[] mappers, Semaphore gate) { |
| this.mappers = mappers; |
| this.gate = gate; |
| } |
| |
| public void run() { |
| gate.release(mappers.length); |
| for (Mapper m : mappers) { |
| m.interrupt(); |
| } |
| } |
| } |
| // the number of mapper threads to start |
| private static final int MAPPER_COUNT = 4; |
| |
| public static void main(String[] args) throws Exception { |
| Path file = Paths.get("data.txt"); |
| FileChannel.open(file, CREATE, TRUNCATE_EXISTING, WRITE).close(); |
| |
| Mapper[] mappers = new Mapper[MAPPER_COUNT]; |
| |
| for (int i=1; i<=20; i++) { |
| System.out.format("Iteration: %s%n", i); |
| |
| FileChannel fc = FileChannel.open(file); |
| boolean failed = false; |
| |
| Semaphore gate = new Semaphore(0); |
| // start mapper threads |
| for (int j=0; j<MAPPER_COUNT; j++) { |
| mappers[j] = Mapper.startMapper(fc, gate); |
| } |
| |
| // interrupt and wait for the mappers to terminate |
| Interruptor interruptor = new Interruptor(mappers, gate); |
| interruptor.start(); |
| try { |
| interruptor.join(10000); |
| if (interruptor.isAlive()) { |
| System.err.println("Interruptor thread did not terminate:"); |
| Throwable t = new Exception("Stack trace"); |
| t.setStackTrace(interruptor.getStackTrace()); |
| t.printStackTrace(); |
| failed = true; |
| } |
| } catch (InterruptedException x) { |
| System.err.println("Main thread was interrupted"); |
| failed = true; |
| } |
| |
| for (Mapper m: mappers) { |
| try { |
| m.join(10000); |
| Exception e = m.exception(); |
| if (e != null) { |
| System.err.println("Mapper thread failed with: " + e); |
| failed = true; |
| } else if (m.isAlive()) { |
| System.err.println("Mapper thread did not terminate:"); |
| Throwable t = new Exception("Stack trace"); |
| t.setStackTrace(m.getStackTrace()); |
| t.printStackTrace(); |
| failed = true; |
| } |
| } catch (InterruptedException x) { |
| System.err.println("Main thread was interrupted"); |
| failed = true; |
| } |
| } |
| |
| if (failed) |
| throw new RuntimeException("Test failed - see log for details"); |
| else |
| fc.close(); |
| } |
| } |
| } |