import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.function.ToIntFunction;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Collectors utilities for {@code common.collect} internals. */
@GwtCompatible

   * 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(

  private void writeObject(ObjectOutputStream stream) throws IOException {
    stream.defaultWriteObject();
    stream.writeInt(size());
    for (E e : this) {
      stream.writeObject(e);
    }
  }

  @SuppressWarnings("unchecked")
  @J2ktIncompatible
  private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();

package com.google.common.io;

import static com.google.common.base.StandardSystemProperty.OS_NAME;
import static com.google.common.io.RecursiveDeleteOption.ALLOW_INSECURE;
import static com.google.common.jimfs.Feature.SECURE_DIRECTORY_STREAM;
import static com.google.common.jimfs.Feature.SYMBOLIC_LINKS;
import static com.google.common.truth.Truth.assertThat;
import static java.nio.charset.StandardCharsets.UTF_8;
import static java.nio.file.LinkOption.NOFOLLOW_LINKS;

import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.Map;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**

import java.io.Serializable;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.stream.Collector;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link Table} whose contents will never change, with many other important properties detailed

  /** The Greek letter delta, used in unicode testing. */
  private static final String DELTA = "\u0394";

  /** A domain part which is valid under lenient validation, but invalid under strict validation. */
  static final String LOTS_OF_DELTAS = Strings.repeat(DELTA, 62);

  private static final String ALMOST_TOO_MANY_LEVELS = Strings.repeat("a.", 127);

    @Override
    Object writeReplace() {
      return new KeysSerializedForm(ImmutableMultimap.this);
    }

    @GwtIncompatible
    @J2ktIncompatible
    private void readObject(ObjectInputStream stream) throws InvalidObjectException {
      throw new InvalidObjectException("Use KeysSerializedForm");
    }
  }

  @GwtIncompatible
  @J2ktIncompatible

   * 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.
   */
  // TODO(kevinb): how to omit that last sentence when building GWT javadoc?

    @Override
    Object writeReplace() {
      return new KeysSerializedForm(ImmutableMultimap.this);
    }

    @GwtIncompatible
    @J2ktIncompatible
    private void readObject(ObjectInputStream stream) throws InvalidObjectException {
      throw new InvalidObjectException("Use KeysSerializedForm");
    }
  }

  @GwtIncompatible
  @J2ktIncompatible