import com.google.common.annotations.GwtCompatible;
import java.util.List;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates sets, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestListGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  List<E> create(Object... elements);

import java.util.Collection;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates collections, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestCollectionGenerator<E extends @Nullable Object>

import com.google.common.annotations.GwtCompatible;
import java.util.List;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates sets, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestListGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  List<E> create(Object... elements);

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.SampleElements.Chars;
import java.util.List;

/**
 * Generates {@code List<Character>} instances for test suites.
 *
 * @author Kevin Bourrillion
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestCharacterListGenerator implements TestListGenerator<Character> {
  @Override

import java.util.Collection;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates collections, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestCollectionGenerator<E extends @Nullable Object>

import com.google.common.annotations.GwtCompatible;
import java.util.Set;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates sets, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestSetGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  Set<E> create(Object... elements);

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.SampleElements.Strings;
import java.util.List;

/**
 * TODO: javadoc.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestStringListGenerator implements TestListGenerator<String> {
  @Override
  public SampleElements<String> samples() {

import java.util.Spliterator;
import java.util.function.Consumer;
import javax.annotation.CheckForNull;

/**
 * {@code keySet()} implementation for {@link ImmutableMap}.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class ImmutableMapKeySet<K, V> extends IndexedImmutableSet<K> {
  private final ImmutableMap<K, V> map;

import org.checkerframework.checker.nullness.qual.Nullable;
import org.junit.Ignore;

/**
 * Base class for collection testers.
 *
 * @param <E> the element type of the collection to be tested.
 * @author Kevin Bourrillion
 */
@GwtCompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@ElementTypesAreNonnullByDefault

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.SampleElements.Chars;
import java.util.List;

/**
 * Generates {@code List<Character>} instances for test suites.
 *
 * @author Kevin Bourrillion
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestCharacterListGenerator implements TestListGenerator<Character> {
  @Override