if (!cls.isInterface()) {
        classes.add(cls);
      }
    }
    return classes;
  }

  private static boolean hasTest(Class<?> testClass, Iterable<String> testNames) {
    for (String testName : testNames) {
      try {
        testClass.getMethod(testName);
        return true;
      } catch (NoSuchMethodException e) {
        continue;
      }
    }
    return false;
  }

import java.util.List;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;

/**
 * Unit test for {@link LinkedHashMultiset}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public class LinkedHashMultisetTest extends TestCase {

  @J2ktIncompatible
  @GwtIncompatible // suite

import java.util.Set;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code ForwardingSet}.
 *
 * @author Robert Konigsberg
 * @author Louis Wasserman
 */
@NullUnmarked
public class ForwardingSetTest extends TestCase {
  static class StandardImplForwardingSet<T> extends ForwardingSet<T> {

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

/**
 * Unit test for {@link ComparisonChain}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public class ComparisonChainTest extends TestCase {
  private static final DontCompareMe DONT_COMPARE_ME = new DontCompareMe();

import com.google.common.base.Strings;
import java.util.Arrays;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Unit test for FarmHashFingerprint64.
 *
 * @author Kyle Maddison
 * @author Geoff Pike
 */
@NullUnmarked
public class FarmHashFingerprint64Test extends TestCase {

  private static final HashFunction HASH_FN = Hashing.farmHashFingerprint64();

import java.util.Arrays;
import java.util.Comparator;
import java.util.List;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;

/**
 * Unit test for {@link SignedBytes}.
 *
 * @author Kevin Bourrillion
 */
@NullMarked
@GwtCompatible
public class SignedBytesTest extends TestCase {
  private static final byte[] EMPTY = {};
  private static final byte[] ARRAY1 = {(byte) 1};

import java.util.Iterator;
import java.util.LinkedList;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link Synchronized#deque} and {@link Queues#synchronizedDeque}.
 *
 * @author Kurt Alfred Kluever
 */
@NullUnmarked
public class SynchronizedDequeTest extends TestCase {

  protected Deque<String> create() {

import java.util.List;
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() {

import java.math.MathContext;
import java.math.RoundingMode;
import java.util.EnumMap;
import java.util.EnumSet;
import java.util.Map;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

@GwtIncompatible
@NullUnmarked
public class BigDecimalMathTest extends TestCase {
  private static final class RoundToDoubleTester {
    private final BigDecimal input;

   * Registers a TearDown implementor which will be run after the test proper.
   *
   * <p>In JUnit4 language, that means as an {@code @After}.
   *
   * <p>In JUnit3 language, that means during the {@link junit.framework.TestCase#tearDown()} step.
   */
  void addTearDown(TearDown tearDown);