* <p>Note: If a parameter is set to {@code null}, the corresponding ThreadLocal variable is removed.</p>
 */
public final class CrawlingParameterUtil {
    private static final ThreadLocal<UrlQueue<?>> URL_QUEUE_THREAD_LOCAL = new ThreadLocal<>();

    private static final ThreadLocal<CrawlerContext> ROBOT_CONTEXT_THREAD_LOCAL = new ThreadLocal<>();

    /** Constant for Kryo serializer type. */
    protected static final String KRYO = "kryo";

    /** ThreadLocal container for Kryo instances to ensure thread safety. */
    protected final ThreadLocal<Kryo> kryoThreadLocal;

    /**
     * Constructs a new DataSerializer.
     * <p>
     * Initializes the ThreadLocal Kryo instances with appropriate configuration.

    /** Per-thread queue of events to dispatch. */
    @SuppressWarnings("ThreadLocalUsage") // Each Dispatcher needs its own state.
    private final ThreadLocal<Queue<Event>> queue =
        new ThreadLocal<Queue<Event>>() {
          @Override
          protected Queue<Event> initialValue() {
            return new ArrayDeque<>();
          }
        };

      }
    }
  }

  /**
   * ThreadLocal holding a single-slot int array holding hash code. Unlike the JDK8 version of this
   * class, we use a suboptimal int[] representation to avoid introducing a new type that can impede
   * class-unloading when ThreadLocals are not removed.
   */
  static final ThreadLocal<int @Nullable []> threadHashCode = new ThreadLocal<>();

  /** Generator of new random hash codes */

        public void run() {}
      };

  public void testDirectExecutorServiceServiceInThreadExecution() throws Exception {
    ListeningExecutorService executor = newDirectExecutorService();
    ThreadLocal<Integer> threadLocalCount =
        new ThreadLocal<Integer>() {
          @Override
          protected Integer initialValue() {
            return 0;
          }
        };

     */
    protected Set<String> robotsTxtUrlSet = new LruHashSet<>(10000);

    /**
     * Thread-local storage for sitemaps.
     */
    protected ThreadLocal<String[]> sitemapsLocal = new ThreadLocal<>();

    /** The number of threads used by the crawler */
    protected int numOfThread = 10;

    /** The maximum number of times to check for active threads. */

  }

  private abstract static class FileFactory {

    private static final Logger logger = Logger.getLogger(FileFactory.class.getName());

    private final ThreadLocal<File> fileThreadLocal = new ThreadLocal<>();

    File createFile() throws IOException {
      File file = File.createTempFile("SinkSourceFile", "txt");
      fileThreadLocal.set(file);
      return file;
    }

   *
   * <p>This class would certainly be simpler and easier to reason about if it were built with
   * ThreadLocal; however, ThreadLocal is not well optimized for the case where the ThreadLocal is
   * non-static, and is initialized/removed frequently - this causes churn in the Thread specific
   * hashmaps. Using a static ThreadLocal to avoid that overhead would mean that different

package com.google.common.escape;

/**
 * @author Jesse Wilson
 */
final class Platform {

  private static final char[] CHAR_BUFFER = new char[1024];

  static char[] charBufferFromThreadLocal() {
    // ThreadLocal is not available to GWT, so we always reuse the same
    // instance.  It is always safe to return the same instance because
    // javascript is single-threaded, and only used by blocks that doesn't
    // involve async callbacks.

    protected Map<String, String> metadataXpathMap = new HashMap<>();

    /** Thread-local instance of XPathAPI for thread-safe XPath evaluation. */
    private final ThreadLocal<XPathAPI> xpathAPI = new ThreadLocal<>();

    /**
     * Creates a new HtmlExtractor instance.
     */
    public HtmlExtractor() {
        super();
    }

    @Override