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

Example 81 with FileLock

use of java.nio.channels.FileLock in project chatty by chatty.

the class LogFile method tryFile.

/**
 * Tries to open the given file and obtain a lock on it. This may fail when
 * the file is already used by another process, or any other IOException of
 * course.
 *
 * @param file The file to attempt to open.
 * @return Returns true if the file is successfully opened and locked.
 */
private boolean tryFile(File file) {
    try {
        LOGGER.info("Log: Trying to open " + file.getAbsolutePath());
        RandomAccessFile raf = new RandomAccessFile(file, "rw");
        raf.seek(raf.length());
        FileChannel channel = raf.getChannel();
        if (lockFile) {
            FileLock lock = channel.tryLock();
            if (lock != null) {
                writer = new BufferedWriter(Channels.newWriter(channel, CHARSET));
                valid = true;
                return true;
            }
        } else {
            writer = new BufferedWriter(Channels.newWriter(channel, CHARSET));
            valid = true;
            return true;
        }
    } catch (IOException ex) {
        LOGGER.warning("Log: Lock failed (" + file + " / " + ex + ")");
    }
    LOGGER.warning("Log: Lock failed (" + file + ")");
    return false;
}

Example 82 with FileLock

use of java.nio.channels.FileLock in project tez by apache.

the class Fetcher method getLock.

private FileLock getLock() throws OverlappingFileLockException, InterruptedException, IOException {
    File lockFile = localFs.pathToFile(new Path(lockPath, host + ".lock"));
    final boolean created = lockFile.createNewFile();
    if (created == false && !lockFile.exists()) {
        // bail-out cleanly
        return null;
    }
    // invariant - file created (winner writes to this file)
    // caveat: closing lockChannel does close the file (do not double close)
    // JDK7 - TODO: use AsynchronousFileChannel instead of RandomAccessFile
    FileChannel lockChannel = new RandomAccessFile(lockFile, "rws").getChannel();
    FileLock xlock = null;
    xlock = lockChannel.tryLock(0, Long.MAX_VALUE, false);
    if (xlock != null) {
        return xlock;
    }
    lockChannel.close();
    return null;
}

Example 83 with FileLock

use of java.nio.channels.FileLock in project activemq-artemis by apache.

the class LockAbstract method lockCLI.

void lockCLI(File lockPlace) throws Exception {
    if (lockPlace != null) {
        lockPlace.mkdirs();
        if (serverLockFile == null) {
            File fileLock = new File(lockPlace, "cli.lock");
            serverLockFile = new RandomAccessFile(fileLock, "rw");
        }
        try {
            FileLock lock = serverLockFile.getChannel().tryLock();
            if (lock == null) {
                throw new CLIException("Error: There is another process using the server at " + lockPlace + ". Cannot start the process!");
            }
            serverLockLock = lock;
        } catch (OverlappingFileLockException e) {
            throw new CLIException("Error: There is another process using the server at " + lockPlace + ". Cannot start the process!");
        }
    }
}

Example 84 with FileLock

use of java.nio.channels.FileLock in project activemq-artemis by apache.

the class NIOSequentialFile method copyTo.

@Override
public void copyTo(SequentialFile dstFile) throws IOException {
    if (ActiveMQJournalLogger.LOGGER.isDebugEnabled()) {
        ActiveMQJournalLogger.LOGGER.debug("Copying " + this + " as " + dstFile);
    }
    if (isOpen()) {
        throw new IllegalStateException("File opened!");
    }
    if (dstFile.isOpen()) {
        throw new IllegalArgumentException("dstFile must be closed too");
    }
    try (RandomAccessFile src = new RandomAccessFile(getFile(), "rw");
        FileChannel srcChannel = src.getChannel();
        FileLock srcLock = srcChannel.lock()) {
        final long readableBytes = srcChannel.size();
        if (readableBytes > 0) {
            try (RandomAccessFile dst = new RandomAccessFile(dstFile.getJavaFile(), "rw");
                FileChannel dstChannel = dst.getChannel();
                FileLock dstLock = dstChannel.lock()) {
                final long oldLength = dst.length();
                final long newLength = oldLength + readableBytes;
                dst.setLength(newLength);
                final long transferred = dstChannel.transferFrom(srcChannel, oldLength, readableBytes);
                if (transferred != readableBytes) {
                    dstChannel.truncate(oldLength);
                    throw new IOException("copied less then expected");
                }
            }
        }
    }
}

Example 85 with FileLock

use of java.nio.channels.FileLock in project cryptofs by cryptomator.

the class OpenCryptoFileTest method testTryLockDelegatesToChannel.

@Theory
public void testTryLockDelegatesToChannel(boolean shared) throws IOException {
    long position = 383872;
    long size = 48483;
    FileLock lock = mock(FileLock.class);
    when(channel.tryLock(position, size, shared)).thenReturn(lock);
    assertThat(inTest.tryLock(position, size, shared), is(lock));
}