@J2ktIncompatible
  private void writeObject(ObjectOutputStream stream) throws IOException {
    stream.defaultWriteObject();
    stream.writeInt(keySet().size());
    for (K key : keySet()) {
      stream.writeObject(key);
    }
    stream.writeInt(size());
    for (Entry<K, V> entry : entries()) {
      stream.writeObject(entry.getKey());
      stream.writeObject(entry.getValue());
    }
  }

  @J2ktIncompatible
  private void writeObject(ObjectOutputStream stream) throws IOException {
    stream.defaultWriteObject();
    stream.writeInt(keySet().size());
    for (K key : keySet()) {
      stream.writeObject(key);
    }
    stream.writeInt(size());
    for (Entry<K, V> entry : entries()) {
      stream.writeObject(entry.getKey());
      stream.writeObject(entry.getValue());
    }
  }

    return builder().addAll(values).build();
  }

  /** Returns an immutable array containing all the values from {@code stream}, in order. */
  public static ImmutableDoubleArray copyOf(DoubleStream stream) {
    // Note this uses very different growth behavior from copyOf(Iterable) and the builder.
    double[] array = stream.toArray();
    return (array.length == 0) ? EMPTY : new ImmutableDoubleArray(array);
  }

  /**

    return builder().addAll(values).build();
  }

  /** Returns an immutable array containing all the values from {@code stream}, in order. */
  public static ImmutableLongArray copyOf(LongStream stream) {
    // Note this uses very different growth behavior from copyOf(Iterable) and the builder.
    long[] array = stream.toArray();
    return (array.length == 0) ? EMPTY : new ImmutableLongArray(array);
  }

  /**

   * Predicates.instanceOf(ArrayList.class)}, which is inconsistent with equals. (See {@link
   * Iterables#filter(Iterable, Class)} for related functionality.)
   *
   * <p><b>{@code Stream} equivalent:</b> {@link java.util.stream.Stream#filter Stream.filter}.
   */
  // TODO(kevinb): how can we omit that Iterables link when building gwt
  // javadoc?
  public static <E extends @Nullable Object> Collection<E> filter(

import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import javax.annotation.CheckForNull;

/**
 * An {@link InputStream} that concatenates multiple substreams. At most one stream will be open at
 * a time.
 *
 * @author Chris Nokleberg
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
final class MultiInputStream extends InputStream {

   */
  @GwtIncompatible // java.io.ObjectOutputStream
  @J2ktIncompatible
  private void writeObject(ObjectOutputStream stream) throws IOException {
    stream.defaultWriteObject();
    stream.writeInt(size());
    for (Entry<K, V> entry : entries()) {
      stream.writeObject(entry.getKey());
      stream.writeObject(entry.getValue());
    }
  }

  @GwtIncompatible // java.io.ObjectInputStream
  @J2ktIncompatible

 * create the {@code TopKSelector} instance.
 *
 * <p>If your input data is available as a {@link Stream}, prefer passing {@link
 * Comparators#least(int)} to {@link Stream#collect(java.util.stream.Collector)}. If it is available
 * as an {@link Iterable} or {@link Iterator}, prefer {@link Ordering#leastOf(Iterable, int)}.
 *

   */
  public abstract Writer openStream() throws IOException;

  /**
   * Opens a new buffered {@link Writer} for writing to this sink. The returned stream is not
   * required to be a {@link BufferedWriter} in order to allow implementations to simply delegate to
   * {@link #openStream()} when the stream returned by that method does not benefit from additional
   * buffering. This method returns a new, independent writer each time it is called.
   *

import static java.lang.Double.isNaN;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.util.Iterator;
import java.util.stream.DoubleStream;
import java.util.stream.IntStream;
import java.util.stream.LongStream;

/**
 * A mutable object which accumulates double values and tracks some basic statistics over all the