new RegularImmutableMap<>(null, new Object[0], 0);

  /*
   * This is an implementation of ImmutableMap optimized especially for Android, which does not like
   * objects per entry.  Instead we use an open-addressed hash table.  This design is basically
   * equivalent to RegularImmutableSet, save that instead of having a hash table containing the
   * elements directly and null for empty positions, we store indices of the keys in the hash table,

/**
 * Provides static methods for working with {@code Collection} instances.
 *
 * <p><b>Java 8+ users:</b> several common uses for this class are now more comprehensively
 * addressed by the new {@link java.util.stream.Stream} library. Read the method documentation below
 * for comparisons. These methods are not being deprecated, but we gently encourage you to migrate
 * to streams.
 *
 * @author Chris Povirk

 * in the {@link Iterators} class.
 *
 * <p><b>Java 8+ users:</b> several common uses for this class are now more comprehensively
 * addressed by the new {@link java.util.stream.Stream} library. Read the method documentation below
 * for comparisons. This class is not being deprecated, but we gently encourage you to migrate to
 * streams.
 *

    checkArgument(setSize < MAX_TABLE_SIZE, "collection too large");
    return MAX_TABLE_SIZE;
  }

  /**
   * Default implementation of the guts of ImmutableSet.Builder, creating an open-addressed hash
   * table and deduplicating elements as they come, so it only allocates O(max(distinct,
   * expectedCapacity)) rather than O(calls to add).
   *

   * serialize the copy. Other methods similar to this do not implement serialization at all for
   * this reason.
   *
   * <p><b>Java 8+ users:</b> many use cases for this method are better addressed by {@link
   * java.util.stream.Stream#map}. This method is not being deprecated, but we gently encourage you
   * to migrate to streams.
   */

/**
 * Provides static methods for working with {@code Collection} instances.
 *
 * <p><b>Java 8+ users:</b> several common uses for this class are now more comprehensively
 * addressed by the new {@link java.util.stream.Stream} library. Read the method documentation below
 * for comparisons. These methods are not being deprecated, but we gently encourage you to migrate
 * to streams.
 *
 * @author Chris Povirk

   * Iterables#filter(Iterable, Class)} for related functionality.)
   *
   * <p><b>Java 8+ users:</b> many use cases for this method are better addressed by {@link
   * java.util.stream.Stream#filter}. This method is not being deprecated, but we gently encourage
   * you to migrate to streams.
   */

  /**
   * The HTTP <a
   * href="https://iabtechlab.com/wp-content/uploads/2019/06/VAST_4.2_final_june26.pdf">{@code
   * X-Device-IP}</a> header field name. Header used for VAST requests to provide the IP address of
   * the device on whose behalf the request is being made.
   *
   * @since 31.0
   */
  public static final String X_DEVICE_IP = "X-Device-IP";
  /**
   * The HTTP <a