if !utf8.Valid(next) {
		return errInvalidTextEncodingError()
	}

	// Create queue
	r.queue = make(chan *queueItem, runtime.GOMAXPROCS(0))
	r.input = make(chan *queueItem, runtime.GOMAXPROCS(0))
	r.readerWg.Add(1)

	// Start splitter
	go func() {
		defer close(r.input)
		defer close(r.queue)
		defer r.readerWg.Done()
		for {
			q := queueItem{
				input: next,

  @CanIgnoreReturnValue
  public static Set<Feature<?>> addImpliedFeatures(Set<Feature<?>> features) {
    Queue<Feature<?>> queue = new ArrayDeque<>(features);
    while (!queue.isEmpty()) {
      Feature<?> feature = queue.remove();
      for (Feature<?> implied : feature.getImpliedFeatures()) {
        if (features.add(implied)) {
          queue.add(implied);
        }
      }
    }
    return features;
  }

  /**

package com.google.common.collect.testing.testers;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.AbstractCollectionTester;
import java.util.Queue;
import org.junit.Ignore;

/**
 * Base class for queue collection tests.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

package com.google.common.collect.testing.testers;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.AbstractCollectionTester;
import java.util.Queue;
import org.junit.Ignore;

/**
 * Base class for queue collection tests.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

      ReferenceQueue<Object> queue,
      PhantomReference<Object> frqReference) {
    this.queue = queue;

    this.finalizableReferenceClassReference = new WeakReference<>(finalizableReferenceClass);

    // Keep track of the FRQ that started us so we know when to stop.
    this.frqReference = frqReference;
  }

  /** Loops continuously, pulling references off the queue and cleaning them up. */

import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.regex.Pattern;

import org.codelibs.fess.crawler.entity.AccessResultImpl;
import org.codelibs.fess.crawler.entity.UrlQueueImpl;

/**
 * @author shinsuke
 *
 */
public class MemoryDataHelper {
    protected volatile Map<String, Queue<UrlQueueImpl<Long>>> urlQueueMap = new HashMap<>();

        final String url = urlQueue.getUrl();
        if (StringUtil.isBlank(url)) {
            if (logger.isDebugEnabled()) {
                logger.debug("URL is a blank: {}", url);
            }
            return false;
        }

        // check it in queue
        for (final UrlQueue<Long> urlInQueue : urlQueueList) {

            final Queue<SearchLog> queue = searchLogQueue;
            searchLogQueue = new ConcurrentLinkedQueue<>();
            processSearchLogQueue(queue);
        }

        if (!clickLogQueue.isEmpty()) {
            final Queue<ClickLog> queue = clickLogQueue;
            clickLogQueue = new ConcurrentLinkedQueue<>();
            processClickLogQueue(queue);
        }
    }

        }
    }

    @Override
    public OpenSearchUrlQueue poll(final String sessionId) {
        final QueueHolder queueHolder = getQueueHolder(sessionId);
        final Queue<OpenSearchUrlQueue> waitingQueue = queueHolder.waitingQueue;
        final Queue<OpenSearchUrlQueue> crawlingQueue = queueHolder.crawlingQueue;
        OpenSearchUrlQueue urlQueue = waitingQueue.poll();
        if (urlQueue != null) {

import java.util.List;
import java.util.Queue;

/**
 * Create queue of strings for tests.
 *
 * @author Jared Levy
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestStringQueueGenerator implements TestQueueGenerator<String> {
  @Override
  public SampleElements<String> samples() {
    return new Strings();
  }

  @Override
  public Queue<String> create(Object... elements) {