import java.util.logging.Level;
import org.jspecify.annotations.Nullable;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *

import java.util.logging.Level;
import org.jspecify.annotations.Nullable;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *

// row. They have an output for each input row.
//
// Some types of a queries are not valid. For example, an aggregation
// function combined with a row function is meaningless ("AVG(s.Age) +
// s.Salary"). Analysis determines if such a scenario exists so an
// error can be returned.

var (
	// Fatal error for query processing.
	errNestedAggregation      = errors.New("Cannot nest aggregations")

   */
  @CanIgnoreReturnValue
  @Override
  boolean remove(@Nullable Object element);

  /**
   * Adds or removes the necessary occurrences of an element such that the element attains the
   * desired count.
   *
   * @param element the element to add or remove occurrences of; may be null only if explicitly
   *     allowed by the implementation

        return; // give up if someone is calling complete
      }
      Waiter succ;
      while (curr != null) {
        succ = curr.next;
        if (curr.thread != null) { // we aren't unlinking this node, update pred.
          pred = curr;
        } else if (pred != null) { // We are unlinking this node and it has a predecessor.
          pred.next = succ;

/**
 * Represents a request for popular words. This class extends {@link Request} and is parameterized
 * with {@link PopularWordsResponse}. It allows specifying various criteria for retrieving popular words,
 * such as index, size, tags, roles, fields, languages, and exclusion words.
 *
 * <p>Key functionalities include:</p>
 * <ul>
 *   <li>Setting the target index for the search.</li>
 *   <li>Limiting the number of results (size).</li>

import com.google.common.annotations.GwtCompatible;
import org.jspecify.annotations.Nullable;

/**
 * An object that converts literal text into a format safe for inclusion in a particular context
 * (such as an XML document). Typically (but not always), the inverse process of "unescaping" the
 * text is performed automatically by the relevant parser.
 *

  /**
   * Version of {@link IteratorTester} that compares an iterator over a given collection of elements
   * (used as the reference iterator) against a {@code PeekingIterator} that *wraps* such an
   * iterator (used as the target iterator).
   *
   * <p>This IteratorTester makes copies of the master so that it can later verify that {@link

    return delegate().descendingMultiset();
  }

  /**
   * A skeleton implementation of a descending multiset view. Normally, {@link
   * #descendingMultiset()} will not reflect any changes you make to the behavior of methods such as
   * {@link #add(Object)} or {@link #pollFirstEntry}. This skeleton implementation correctly
   * delegates each of its operations to the appropriate methods of this {@code
   * ForwardingSortedMultiset}.
   *

import org.lastaflute.web.util.LaRequestUtil;

import jakarta.annotation.PostConstruct;

/**
 * The helper for user activities.
 * This class provides methods to log user actions such as login, logout, and access.
 * It supports both LTSV and ECS log formats.
 *
 */
public class ActivityHelper {

    /**
     * Default constructor.
     */
    public ActivityHelper() {