* @param executor the executor in which the listeners callback methods will be run. For fast,
   *     lightweight listeners that would be safe to execute in any thread, consider {@link
   *     MoreExecutors#directExecutor}.
   * @since 13.0
   */
  void addListener(Listener listener, Executor executor);

  /**
   * The lifecycle states of a service.
   *

        ComponentUtil.getCrawlingConfigHelper().store("test", webConfig);
        setValueToObject(ComponentUtil.getLabelTypeHelper(), "labelTypePatternList", new ArrayList<LabelTypePattern>());

        System.gc();
        Thread.sleep(1000L);
        long current = MemoryUtil.getUsedMemory();
        for (int i = 0; i < 10000; i++) {
            if (i % 1000 == 0) {
                logger.info("count:" + i + ", " + MemoryUtil.getMemoryUsageLog());

import org.codelibs.fess.opensearch.config.exentity.CrawlingConfig.ConfigName;
import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.DocumentUtil;

/**
 * FessCrawlerThread is a specialized crawler thread implementation for the Fess search engine.
 * This class extends the base CrawlerThread and provides Fess-specific functionality for
 * crawling and indexing documents, including incremental crawling capabilities, content

   *
   * <p>Note that you cannot always tell if an attempt to insert an element will succeed by
   * inspecting {@code remainingCapacity} because it may be the case that another thread is about to
   * insert or remove an element.
   */
  @CanIgnoreReturnValue
  @Override
  public int remainingCapacity() {
    Monitor monitor = this.monitor;
    monitor.enter();
    try {

import java.util.stream.LongStream;

/**
 * A mutable object which accumulates double values and tracks some basic statistics over all the
 * values added so far. The values may be added singly or in groups. This class is not thread safe.
 *
 * @author Pete Gillin
 * @author Kevin Bourrillion
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class StatsAccumulator {
  /** Creates a new accumulator. */

 *       appropriate factory method for details. View collections such as {@link
 *       ImmutableMultiset#elementSet} iterate in the same order as the parent, except as noted.
 *   <li><b>Thread safety.</b> It is safe to access this collection concurrently from multiple
 *       threads.
 *   <li><b>Integrity.</b> This type cannot be subclassed outside this package (which would allow

    This simple option dramatically changes the behavior of the request body and of the entire
    call.

    The `RequestBody.writeTo()` method may now retain a reference to the provided sink and
    hand it off to another thread to write to it after `writeTo` returns.

    The `EventListener` may now see requests and responses interleaved in ways not previously
    permitted. For example, a listener may receive `responseHeadersStart()` followed by

      assertThrows(
          NullPointerException.class, () -> builder.addAll((Iterable<String>) iterableWithNulls));
    }
  }

  /**
   * Verify thread safety by using a collection whose size() may be inconsistent with the actual
   * number of elements and whose elements may change over time.
   *

   * element (the given list itself).
   *
   * <p>This method is safe to use even when {@code elements} is a synchronized or concurrent
   * collection that is currently being modified by another thread.
   *
   * @throws NullPointerException if {@code elements} contains a null element
   */
  public static <E> ImmutableList<E> copyOf(Collection<? extends E> elements) {
    if (elements instanceof ImmutableCollection) {

   * values.
   *
   * <p>Elements are copied from the argument collection as if by {@code collection.toArray()}.
   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Character} objects
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives