public void deleteBadWord(final String badWord) {
        suggester.indexer().deleteBadWord(badWord);
        refresh();
    }

    /**
     * Refreshes the suggest index.
     */
    public synchronized void refresh() {
        suggester.refresh();
        if (popularWordHelper != null) {
            popularWordHelper.clearCache();
        }
    }

    /**

                    startLatch.await(); // Wait for signal to start
                    conn.connect();
                    successCount.incrementAndGet();
                } catch (Exception e) {
                    synchronized (exceptions) {
                        exceptions.add(e);
                    }
                    failureCount.incrementAndGet();
                } finally {
                    doneLatch.countDown();

As the execution time is consumed mostly by waiting for <abbr title="Input and Output">I/O</abbr> operations, they call them "I/O bound" operations.

It's called "asynchronous" because the computer / program doesn't have to be "synchronized" with the slow task, waiting for the exact moment that the task finishes, while doing nothing, to be able to take the task result and continue the work.

                            assertTrue(CrawlerStatus.INITIALIZING.compareTo(CrawlerStatus.DONE) < 0);
                        }
                    } catch (Exception e) {
                        synchronized (exceptions) {
                            exceptions.add(e);
                        }
                    }
                }
            });
        }

        // Start all threads

     *            if there is a DCE/RPC protocol error
     * @throws IOException
     *            if there is an I/O error during binding
     */
    public void bind() throws DcerpcException, IOException {
        synchronized (this) {
            try {
                this.state = 1;
                final DcerpcMessage bind = new DcerpcBind(this.binding, this);
                sendrecv(bind);
            } catch (final IOException ioe) {

    public SmbClient() {
        super();
    }

    /**
    * Initializes the SMB client.
    * @see org.codelibs.fess.crawler.client.AbstractCrawlerClient#init()
    */
    @Override
    public synchronized void init() {
        if (smbAuthenticationHolder != null) {
            return;
        }

        if (logger.isDebugEnabled()) {
            logger.debug("Initializing SmbClient...");
        }

    public int available() throws IOException {
      return (int) min(in.available(), left);
    }

    // it's okay to mark even if mark isn't supported, as reset won't work
    @Override
    public synchronized void mark(int readLimit) {
      in.mark(readLimit);
      mark = left;
    }

    @Override
    public int read() throws IOException {
      if (left == 0) {
        return -1;
      }

     *
     * @return The configured SPNEGO authenticator instance
     * @throws SsoLoginException if SPNEGO initialization fails
     */
    protected synchronized org.codelibs.spnego.SpnegoAuthenticator getAuthenticator() {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();

        final Queue<OpenSearchUrlQueue> crawlingQueue = queueHolder.crawlingQueue;

        OpenSearchUrlQueue urlQueue = waitingQueue.poll();
        if (urlQueue == null) {
            synchronized (queueHolder) {
                urlQueue = waitingQueue.poll();
                if (urlQueue == null) {
                    final List<OpenSearchUrlQueue> urlQueueList = fetchUrlQueueList(sessionId);

            if (totalProjects <= 1) {
                infoMain(building);
            } else {
                // display progress [i/n]
                int number;
                synchronized (this) {
                    number = ++currentVisitedProjectCount;
                }
                String progress = " [" + number + '/' + totalProjects + ']';