private static <E> Iterator<E> asIterator(E... elements) {
    return asList(elements).iterator();
  }

  // In GWT, java.util.TreeSet throws ClassCastException when the comparator
  // throws it, unlike the JDK.  Therefore, we accept ClassCastException as a
  // valid result thrown by java.util.TreeSet#equals.
  private static void assertNotEqualLenient(TreeSet<?> unexpected, SortedSet<?> actual) {
    try {

   *       collections intelligently fall back to a binary search tree if hash table collisions are
   *       detected. Rather than going to all the trouble of reimplementing this ourselves, we
   *       simply switch over to use the JDK implementation wholesale if probable hash flooding is
   *       detected, sacrificing the compactness guarantee in very rare cases in exchange for much
   *       more reliable worst-case behavior.

 * the rest not null -- and the test fails if no expected exception is thrown. {@code
 * NullPointerTester} uses best effort to pick non-null default values for many common JDK and Guava
 * types, and also for interfaces and public classes that have public parameter-less constructors.
 * When the non-null default value for a particular parameter type cannot be provided by {@code

    assertThat(Booleans.falseFirst().compare(false, true)).isLessThan(0);
    assertThat(Booleans.falseFirst().compare(true, false)).isGreaterThan(0);
  }

  // We need to test that our method behaves like the JDK method.
  @SuppressWarnings("InlineMeInliner")
  public void testCompare() {
    for (boolean x : VALUES) {
      for (boolean y : VALUES) {
        // note: spec requires only that the sign is the same

   *       collections intelligently fall back to a binary search tree if hash table collisions are
   *       detected. Rather than going to all the trouble of reimplementing this ourselves, we
   *       simply switch over to use the JDK implementation wholesale if probable hash flooding is
   *       detected, sacrificing the compactness guarantee in very rare cases in exchange for much
   *       more reliable worst-case behavior.

    public boolean removeAll(Collection<?> c) {
      if (c.isEmpty()) {
        return false;
      }
      int oldSize = size(); // calls refreshIfEmpty

      // Guava issue 1013: AbstractSet and most JDK set implementations are
      // susceptible to quadratic removeAll performance on lists;
      // use a slightly smarter implementation here
      boolean changed = Sets.removeAllImpl((Set<V>) delegate, c);

- **User Permissions**: Access control and label configurations

### 2. Infrastructure Requirements

Ensure your Fess environment meets these requirements:

- **Java**: JDK 17 or later
- **Memory**: Minimum 4GB RAM (8GB+ recommended for production)
- **Storage**: At least 2x your current index size
- **Network**: Access to crawl sources (web servers, file shares, databases)

 * calculate <i>only</i> the mean.
 *
 * <p><b>Java 8+ users:</b> If you are not using any of the variance statistics, you may wish to use
 * built-in JDK libraries instead of this class.
 *
 * @author Pete Gillin
 * @author Kevin Bourrillion
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class Stats implements Serializable {

 *
 * <p><b>Important note:</b> Unlike {@code InetAddress.getByName()}, the methods of this class never
 * cause DNS services to be accessed. For this reason, you should prefer these methods as much as
 * possible over their JDK equivalents whenever you are expecting to handle only IP address string
 * literals -- there is no blocking DNS penalty for a malformed string.
 *

   *       collections intelligently fall back to a binary search tree if hash table collisions are
   *       detected. Rather than going to all the trouble of reimplementing this ourselves, we
   *       simply switch over to use the JDK implementation wholesale if probable hash flooding is
   *       detected, sacrificing the compactness guarantee in very rare cases in exchange for much
   *       more reliable worst-case behavior.