import java.util.Set;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link Optional}.
 *
 * @author Kurt Alfred Kluever
 */
@NullMarked
@GwtCompatible
public final class OptionalTest extends TestCase {
  @SuppressWarnings("NullOptional")
  public void testToJavaUtil_static() {
    assertThat(Optional.toJavaUtil(null)).isNull();

import org.jspecify.annotations.Nullable;
import sun.security.jca.ProviderList;
import sun.security.jca.Providers;

/**
 * Tests for the MacHashFunction.
 *
 * @author Kurt Alfred Kluever
 */
@NullUnmarked
public class MacHashFunctionTest extends TestCase {

  private static final ImmutableSet<String> INPUTS = ImmutableSet.of("", "Z", "foobar");

  private static final SecretKey MD5_KEY =

 *
 * <p>Important: the order of the constants cannot change, and they cannot be deleted - we depend on
 * their ordinal for BloomFilter serialization.
 *
 * @author Dimitris Andreou
 * @author Kurt Alfred Kluever
 */
enum BloomFilterStrategies implements BloomFilter.Strategy {
  /**
   * See "Less Hashing, Same Performance: Building a Better Bloom Filter" by Adam Kirsch and Michael

import org.jspecify.annotations.Nullable;
import sun.security.jca.ProviderList;
import sun.security.jca.Providers;

/**
 * Tests for the MacHashFunction.
 *
 * @author Kurt Alfred Kluever
 */
@NullUnmarked
public class MacHashFunctionTest extends TestCase {

  private static final ImmutableSet<String> INPUTS = ImmutableSet.of("", "Z", "foobar");

  private static final SecretKey MD5_KEY =

 *     this type, so it is safe to cast an {@code Optional<T>} to {@code Optional<S>} for any
 *     supertype {@code S} of {@code T}.
 * @author Kurt Alfred Kluever
 * @author Kevin Bourrillion
 * @since 10.0
 */
@DoNotMock("Use Optional.of(value) or Optional.absent()")
@GwtCompatible
public abstract class Optional<T> implements Serializable {
  /**

import java.io.Serializable;
import org.jspecify.annotations.Nullable;

/**
 * An immutable hash code of arbitrary bit length.
 *
 * @author Dimitris Andreou
 * @author Kurt Alfred Kluever
 * @since 11.0
 */
public abstract class HashCode {
  HashCode() {}

  /** Returns the number of bits in this hash code; a positive multiple of 8. */
  public abstract int bits();

  /**

import java.io.Serializable;
import org.jspecify.annotations.Nullable;

/**
 * An immutable hash code of arbitrary bit length.
 *
 * @author Dimitris Andreou
 * @author Kurt Alfred Kluever
 * @since 11.0
 */
public abstract class HashCode {
  HashCode() {}

  /** Returns the number of bits in this hash code; a positive multiple of 8. */
  public abstract int bits();

  /**

/**
 * Static utility methods pertaining to {@link Queue} and {@link Deque} instances. Also see this
 * class's counterparts {@link Lists}, {@link Sets}, and {@link Maps}.
 *
 * @author Kurt Alfred Kluever
 * @since 11.0
 */
@GwtCompatible
public final class Queues {
  private Queues() {}

  // ArrayBlockingQueue

  /**

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

/**
 * Various utilities for testing {@link HashFunction}s.
 *
 * @author Dimitris Andreou
 * @author Kurt Alfred Kluever
 */
@NullUnmarked
final class HashTestUtils {
  private HashTestUtils() {}

  /** Converts a string, which should contain only ascii-representable characters, to a byte[]. */
  static byte[] ascii(String string) {

import java.nio.ByteBuffer;

/**
 * This class generates a CRC32C checksum, defined by RFC 3720, Section 12.1. The generator
 * polynomial for this checksum is {@code 0x11EDC6F41}.
 *
 * @author Kurt Alfred Kluever
 */
@Immutable
final class Crc32cHashFunction extends AbstractHashFunction {
  static final HashFunction CRC_32_C = new Crc32cHashFunction();

  @Override
  public int bits() {
    return 32;
  }