* that every {@code Runnable} that is {@linkplain #add added} will be executed after {@link
 * #execute()} is called. Any {@code Runnable} added after the call to {@code execute} is still
 * guaranteed to execute. There is no guarantee, however, that listeners will be executed in the
 * order that they are added.
 *
 * <p>Exceptions thrown by a listener will be propagated up to the executor. Any exception thrown

 * equivalent elements are added to it, it is undefined which will come first in the output.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class TopKSelector<
    T extends @Nullable Object> {

  /**
   * Returns a {@code TopKSelector} that collects the lowest {@code k} elements added to it,

   */
  public static <E> Builder<E> builder() {
    return new Builder<>();
  }

  /**
   * Returns a new builder, expecting the specified number of elements to be added.
   *
   * <p>If {@code expectedSize} is exactly the number of elements added to the builder before {@link
   * Builder#build} is called, the builder is likely to perform better than an unsized {@link
   * #builder()} would have.
   *

    }

    /**
     * Adds {@code element} to the {@code ImmutableSortedSet}. If the {@code ImmutableSortedSet}
     * already contains {@code element}, then {@code add} has no effect. (only the previously added
     * element is retained).
     *
     * @param element the element to add
     * @return this {@code Builder} object
     * @throws NullPointerException if {@code element} is null
     */

   * omitted} or {@linkplain #withPadChar(char) replaced}.
   *
   * <p>No line feeds are added by default, as per <a
   * href="http://tools.ietf.org/html/rfc4648#section-3.1">RFC 4648 section 3.1</a>, Line Feeds in
   * Encoded Data. Line feeds may be added using {@link #withSeparator(String, int)}.
   */
  public static BaseEncoding base64() {
    return BASE64;
  }

    ImmutableSet<String> set = this.<String>builder().addAll(a).addAll(b).build();
    assertThat(set).containsExactly("a", "b", "c", "d", "e").inOrder();
  }

  static final int LAST_COLOR_ADDED = 0x00BFFF;

  public void testComplexBuilder() {
    List<Integer> colorElem = asList(0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF);
    // javac won't compile this without "this.<Integer>"

    ImmutableSet<String> set = this.<String>builder().addAll(a).addAll(b).build();
    assertThat(set).containsExactly("a", "b", "c", "d", "e").inOrder();
  }

  static final int LAST_COLOR_ADDED = 0x00BFFF;

  public void testComplexBuilder() {
    List<Integer> colorElem = asList(0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF);
    // javac won't compile this without "this.<Integer>"

   */
  public static <K, V> Builder<K, V> builder() {
    return new Builder<>();
  }

  /**
   * Returns a new builder, expecting the specified number of entries to be added.
   *
   * <p>If {@code expectedSize} is exactly the number of entries added to the builder before {@link
   * Builder#build} is called, the builder is likely to perform better than an unsized {@link
   * #builder()} would have.
   *

   */
  public static <K, V> Builder<K, V> builder() {
    return new Builder<>();
  }

  /**
   * Returns a new builder, expecting the specified number of entries to be added.
   *
   * <p>If {@code expectedSize} is exactly the number of entries added to the builder before {@link
   * Builder#build} is called, the builder is likely to perform better than an unsized {@link
   * #builder()} would have.
   *

    Builder<K, V> combine(Builder<K, V> builder) {
      entries.addAll(builder.entries);
      return this;
    }

    /**
     * Returns an {@code ImmutableRangeMap} containing the associations previously added to this
     * builder.
     *
     * @throws IllegalArgumentException if any two ranges inserted into this builder overlap
     */
    public ImmutableRangeMap<K, V> build() {