Examples with FileChannel java.nio.channels.FileChannel used on opensource projects

Example 1 with FileChannel

use of java.nio.channels.FileChannel in project camel by apache.

the class FileLockExclusiveReadLockStrategy method acquireExclusiveReadLock.

@Override
public boolean acquireExclusiveReadLock(GenericFileOperations<File> operations, GenericFile<File> file, Exchange exchange) throws Exception {
    // must call super
    if (!super.acquireExclusiveReadLock(operations, file, exchange)) {
        return false;
    }
    File target = new File(file.getAbsoluteFilePath());
    LOG.trace("Waiting for exclusive read lock to file: {}", target);
    FileChannel channel = null;
    RandomAccessFile randomAccessFile = null;
    boolean exclusive = false;
    FileLock lock = null;
    try {
        randomAccessFile = new RandomAccessFile(target, "rw");
        // try to acquire rw lock on the file before we can consume it
        channel = randomAccessFile.getChannel();
        StopWatch watch = new StopWatch();
        while (!exclusive) {
            // timeout check
            if (timeout > 0) {
                long delta = watch.taken();
                if (delta > timeout) {
                    CamelLogger.log(LOG, readLockLoggingLevel, "Cannot acquire read lock within " + timeout + " millis. Will skip the file: " + target);
                    // we could not get the lock within the timeout period, so return false
                    return false;
                }
            }
            // get the lock using either try lock or not depending on if we are using timeout or not
            try {
                lock = timeout > 0 ? channel.tryLock() : channel.lock();
            } catch (IllegalStateException ex) {
            // Also catch the OverlappingFileLockException here. Do nothing here                    
            }
            if (lock != null) {
                LOG.trace("Acquired exclusive read lock: {} to file: {}", lock, target);
                exclusive = true;
            } else {
                boolean interrupted = sleep();
                if (interrupted) {
                    // we were interrupted while sleeping, we are likely being shutdown so return false
                    return false;
                }
            }
        }
    } catch (IOException e) {
        // such as AntiVirus or MS Office that has special locks for it's supported files
        if (timeout == 0) {
            // if not using timeout, then we cant retry, so return false
            return false;
        }
        LOG.debug("Cannot acquire read lock. Will try again.", e);
        boolean interrupted = sleep();
        if (interrupted) {
            // we were interrupted while sleeping, we are likely being shutdown so return false
            return false;
        }
    } finally {
        // close channels if we did not grab the lock
        if (!exclusive) {
            IOHelper.close(channel, "while acquiring exclusive read lock for file: " + target, LOG);
            IOHelper.close(randomAccessFile, "while acquiring exclusive read lock for file: " + target, LOG);
            // and also must release super lock
            super.releaseExclusiveReadLockOnAbort(operations, file, exchange);
        }
    }
    // store read-lock state
    exchange.setProperty(asReadLockKey(file, Exchange.FILE_LOCK_EXCLUSIVE_LOCK), lock);
    exchange.setProperty(asReadLockKey(file, Exchange.FILE_LOCK_RANDOM_ACCESS_FILE), randomAccessFile);
    // we grabbed the lock
    return true;
}

Example 2 with FileChannel

use of java.nio.channels.FileChannel in project camel by apache.

the class FileOperations method writeFileByStream.

private void writeFileByStream(InputStream in, File target) throws IOException {
    FileChannel out = null;
    try {
        out = prepareOutputFileChannel(target);
        LOG.debug("Using InputStream to write file: {}", target);
        int size = endpoint.getBufferSize();
        byte[] buffer = new byte[size];
        ByteBuffer byteBuffer = ByteBuffer.wrap(buffer);
        int bytesRead;
        while ((bytesRead = in.read(buffer)) != -1) {
            if (bytesRead < size) {
                byteBuffer.limit(bytesRead);
            }
            out.write(byteBuffer);
            byteBuffer.clear();
        }
    } finally {
        IOHelper.close(in, target.getName(), LOG);
        IOHelper.close(out, target.getName(), LOG, endpoint.isForceWrites());
    }
}

Example 3 with FileChannel

use of java.nio.channels.FileChannel in project camel by apache.

the class FileUtil method copyFile.

/**
     * Copies the file
     *
     * @param from  the source file
     * @param to    the destination file
     * @throws IOException If an I/O error occurs during copy operation
     */
public static void copyFile(File from, File to) throws IOException {
    FileChannel in = null;
    FileChannel out = null;
    try {
        in = new FileInputStream(from).getChannel();
        out = new FileOutputStream(to).getChannel();
        if (LOG.isTraceEnabled()) {
            LOG.trace("Using FileChannel to copy from: " + in + " to: " + out);
        }
        long size = in.size();
        long position = 0;
        while (position < size) {
            position += in.transferTo(position, BUFFER_SIZE, out);
        }
    } finally {
        IOHelper.close(in, from.getName(), LOG);
        IOHelper.close(out, to.getName(), LOG);
    }
}

Example 4 with FileChannel

use of java.nio.channels.FileChannel in project flink by apache.

the class SpilledBufferOrEventSequenceTest method testMultipleSequences.

@Test
public void testMultipleSequences() {
    File secondFile = null;
    FileChannel secondChannel = null;
    try {
        // create the second file channel
        secondFile = File.createTempFile("testdata", "tmp");
        secondChannel = new RandomAccessFile(secondFile, "rw").getChannel();
        final Random rnd = new Random();
        final Random bufferRnd = new Random();
        final long bufferSeed = rnd.nextLong();
        bufferRnd.setSeed(bufferSeed);
        final int numEventsAndBuffers1 = 272;
        final int numEventsAndBuffers2 = 151;
        final int numChannels = 1656;
        final ArrayList<BufferOrEvent> events1 = new ArrayList<BufferOrEvent>(128);
        final ArrayList<BufferOrEvent> events2 = new ArrayList<BufferOrEvent>(128);
        for (int i = 0; i < numEventsAndBuffers1; i++) {
            boolean isEvent = rnd.nextDouble() < 0.05d;
            if (isEvent) {
                events1.add(generateAndWriteEvent(fileChannel, rnd, numChannels));
            } else {
                writeBuffer(fileChannel, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        for (int i = 0; i < numEventsAndBuffers2; i++) {
            boolean isEvent = rnd.nextDouble() < 0.05d;
            if (isEvent) {
                events2.add(generateAndWriteEvent(secondChannel, rnd, numChannels));
            } else {
                writeBuffer(secondChannel, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        // reset and create reader
        fileChannel.position(0L);
        secondChannel.position(0L);
        bufferRnd.setSeed(bufferSeed);
        SpilledBufferOrEventSequence seq1 = new SpilledBufferOrEventSequence(tempFile, fileChannel, buffer, pageSize);
        SpilledBufferOrEventSequence seq2 = new SpilledBufferOrEventSequence(secondFile, secondChannel, buffer, pageSize);
        // read and validate the sequence 1
        seq1.open();
        int numEvent = 0;
        for (int i = 0; i < numEventsAndBuffers1; i++) {
            BufferOrEvent next = seq1.getNext();
            if (next.isEvent()) {
                BufferOrEvent expected = events1.get(numEvent++);
                assertEquals(expected.getEvent(), next.getEvent());
                assertEquals(expected.getChannelIndex(), next.getChannelIndex());
            } else {
                validateBuffer(next, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        assertNull(seq1.getNext());
        assertEquals(events1.size(), numEvent);
        // read and validate the sequence 2
        seq2.open();
        numEvent = 0;
        for (int i = 0; i < numEventsAndBuffers2; i++) {
            BufferOrEvent next = seq2.getNext();
            if (next.isEvent()) {
                BufferOrEvent expected = events2.get(numEvent++);
                assertEquals(expected.getEvent(), next.getEvent());
                assertEquals(expected.getChannelIndex(), next.getChannelIndex());
            } else {
                validateBuffer(next, bufferRnd.nextInt(pageSize) + 1, bufferRnd.nextInt(numChannels));
            }
        }
        assertNull(seq2.getNext());
        assertEquals(events2.size(), numEvent);
    } catch (Exception e) {
        e.printStackTrace();
        fail(e.getMessage());
    } finally {
        if (secondChannel != null) {
            try {
                secondChannel.close();
            } catch (IOException e) {
            // ignore here
            }
        }
        if (secondFile != null) {
            //noinspection ResultOfMethodCallIgnored
            secondFile.delete();
        }
    }
}

Example 5 with FileChannel

use of java.nio.channels.FileChannel in project hadoop by apache.

the class FsDatasetTestUtil method assertFileLockReleased.

/**
   * Asserts that the storage lock file in the given directory has been
   * released.  This method works by trying to acquire the lock file itself.  If
   * locking fails here, then the main code must have failed to release it.
   *
   * @param dir the storage directory to check
   * @throws IOException if there is an unexpected I/O error
   */
public static void assertFileLockReleased(String dir) throws IOException {
    StorageLocation sl = StorageLocation.parse(dir);
    File lockFile = new File(new File(sl.getUri()), Storage.STORAGE_FILE_LOCK);
    try (RandomAccessFile raf = new RandomAccessFile(lockFile, "rws");
        FileChannel channel = raf.getChannel()) {
        FileLock lock = channel.tryLock();
        assertNotNull(String.format("Lock file at %s appears to be held by a different process.", lockFile.getAbsolutePath()), lock);
        if (lock != null) {
            try {
                lock.release();
            } catch (IOException e) {
                FsDatasetImpl.LOG.warn(String.format("I/O error releasing file lock %s.", lockFile.getAbsolutePath()), e);
                throw e;
            }
        }
    } catch (OverlappingFileLockException e) {
        fail(String.format("Must release lock file at %s.", lockFile.getAbsolutePath()));
    }
}