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() {

 *
 * <p>An instance of this class is serializable if its reference is absent or is a serializable
 * object.
 *
 * <p><b>Comparison to {@code java.util.Optional} (JDK 8 and higher):</b> A new {@code Optional}
 * class was added for Java 8. The two classes are extremely similar, but incompatible (they cannot
 * share a common supertype). <i>All</i> known differences are listed either here or with the
 * relevant methods below.
 *
 * <ul>

    /**
     * A queue of elements currently in the map, ordered by write time. Elements are added to the
     * tail of the queue on write.
     */
    @GuardedBy("this")
    final Queue<ReferenceEntry<K, V>> writeQueue;

    /**
     * A queue of elements currently in the map, ordered by access time. Elements are added to the
     * tail of the queue on access (note that writes count as accesses).
     */

    @CanIgnoreReturnValue
    Builder<C> combine(Builder<C> builder) {
      addAll(builder.ranges);
      return this;
    }

    /**
     * Returns an {@code ImmutableRangeSet} containing the ranges added to this builder.
     *
     * @throws IllegalArgumentException if any input ranges have nonempty overlap
     */
    public ImmutableRangeSet<C> build() {
      ImmutableList.Builder<Range<C>> mergedRangesBuilder =

    }
    return accumulator;
  }

  /**
   * Creates a {@link PairedStatsAccumulator} filled with the given lists of {@code x} and {@code y}
   * values, which must be of the same size, added in groups of {@code partitionSize} using {@link
   * PairedStatsAccumulator#addAll(PairedStats)}.
   */
  static PairedStatsAccumulator createPartitionedFilledPairedStatsAccumulator(

    @CanIgnoreReturnValue
    Builder<C> combine(Builder<C> builder) {
      addAll(builder.ranges);
      return this;
    }

    /**
     * Returns an {@code ImmutableRangeSet} containing the ranges added to this builder.
     *
     * @throws IllegalArgumentException if any input ranges have nonempty overlap
     */
    public ImmutableRangeSet<C> build() {
      ImmutableList.Builder<Range<C>> mergedRangesBuilder =

      currentWaiter.unpark();
    }
  }

  /**
   * Clears the {@link #listeners} list and prepends its contents to {@code onto}, least recently
   * added first.
   */
  @CheckForNull
  private Listener clearListeners(@CheckForNull Listener onto) {
    // We need to
    // 1. atomically swap the listeners with TOMBSTONE, this is because addListener uses that

    assertThat(Doubles.tryParse(input)).isEqualTo(expected);
    if (expected != null && !Doubles.FLOATING_POINT_PATTERN.matcher(input).matches()) {
      // TODO(cpovirk): Use SourceCodeEscapers if it is added to Guava.
      StringBuilder escapedInput = new StringBuilder();
      for (char c : input.toCharArray()) {
        if (c >= 0x20 && c <= 0x7E) {
          escapedInput.append(c);
        } else {

    assertThat(Doubles.tryParse(input)).isEqualTo(expected);
    if (expected != null && !Doubles.FLOATING_POINT_PATTERN.matcher(input).matches()) {
      // TODO(cpovirk): Use SourceCodeEscapers if it is added to Guava.
      StringBuilder escapedInput = new StringBuilder();
      for (char c : input.toCharArray()) {
        if (c >= 0x20 && c <= 0x7E) {
          escapedInput.append(c);
        } else {

  }

  /** Runs a runnable without any permissions. */
  public void runWithoutPermissions(Runnable r) {
    runWithPermissions(r);
  }

  /** A security policy where new permissions can be dynamically added or all cleared. */
  public static class AdjustablePolicy extends java.security.Policy {
    Permissions perms = new Permissions();

    AdjustablePolicy(Permission... permissions) {