static final Predicate<Entry<String, Integer>> CORRECT_LENGTH =
      input -> input.getKey().length() == input.getValue();

  abstract Map<String, Integer> createUnfiltered();

  public void testFilteredKeysIllegalPut() {
    Map<String, Integer> unfiltered = createUnfiltered();
    Map<String, Integer> filtered = Maps.filterKeys(unfiltered, NOT_LENGTH_3);
    filtered.put("a", 1);
    filtered.put("b", 2);

  static final Predicate<Entry<String, Integer>> CORRECT_LENGTH =
      input -> input.getKey().length() == input.getValue();

  abstract Map<String, Integer> createUnfiltered();

  public void testFilteredKeysIllegalPut() {
    Map<String, Integer> unfiltered = createUnfiltered();
    Map<String, Integer> filtered = Maps.filterKeys(unfiltered, NOT_LENGTH_3);
    filtered.put("a", 1);
    filtered.put("b", 2);

import java.util.Set;
import org.jspecify.annotations.NullUnmarked;

@NullUnmarked
public final class SetsFilterHashSetTest extends AbstractFilteredSetTest<Set<Integer>> {
  @Override
  Set<Integer> createUnfiltered(Iterable<Integer> contents) {
    return newHashSet(contents);
  }

  @Override
  Set<Integer> filter(Set<Integer> elements, Predicate<? super Integer> predicate) {
    return Sets.filter(elements, predicate);

import org.jspecify.annotations.NullUnmarked;

@NullUnmarked
public final class IterablesFilterArrayListTest
    extends AbstractFilteredIterableTest<Iterable<Integer>> {
  @Override
  Iterable<Integer> createUnfiltered(Iterable<Integer> contents) {
    return Lists.newArrayList(contents);
  }

  @Override
  Iterable<Integer> filter(Iterable<Integer> elements, Predicate<? super Integer> predicate) {

import java.util.NavigableSet;
import org.jspecify.annotations.NullUnmarked;

@NullUnmarked
public final class SetsFilterNavigableSetTest extends AbstractFilteredNavigableSetTest {
  @Override
  NavigableSet<Integer> createUnfiltered(Iterable<Integer> contents) {
    return Sets.newTreeSet(contents);
  }

  @Override
  NavigableSet<Integer> filter(
      NavigableSet<Integer> elements, Predicate<? super Integer> predicate) {

import java.util.NavigableSet;
import org.jspecify.annotations.NullUnmarked;

@NullUnmarked
public final class SetsFilterNavigableSetTest extends AbstractFilteredNavigableSetTest {
  @Override
  NavigableSet<Integer> createUnfiltered(Iterable<Integer> contents) {
    return Sets.newTreeSet(contents);
  }

  @Override
  NavigableSet<Integer> filter(
      NavigableSet<Integer> elements, Predicate<? super Integer> predicate) {

import java.util.Set;
import org.jspecify.annotations.NullUnmarked;

@NullUnmarked
public final class SetsFilterHashSetTest extends AbstractFilteredSetTest<Set<Integer>> {
  @Override
  Set<Integer> createUnfiltered(Iterable<Integer> contents) {
    return newHashSet(contents);
  }

  @Override
  Set<Integer> filter(Set<Integer> elements, Predicate<? super Integer> predicate) {
    return Sets.filter(elements, predicate);