* 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);

import com.google.common.testing.TearDownStack;
import java.util.Random;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@link Monitor}, either interruptible or uninterruptible.
 *
 * @author Justin T. Sampson
 */
@NullUnmarked
public abstract class MonitorTestCase extends TestCase {

  public class TestGuard extends Monitor.Guard {
    private volatile boolean satisfied;

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 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.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};

    assertTrue(len4.matches('d'));
    for (char c = 'e'; c < 'z'; c++) {
      assertFalse(len4.matches(c));
    }

    Random rand = new Random(1234);
    for (int testCase = 0; testCase < 100; testCase++) {
      char[] chars = randomChars(rand, rand.nextInt(63) + 1);
      CharMatcher m = SmallCharMatcher.from(bitSet(chars), new String(chars));
      checkExactMatches(m, chars);
    }
  }

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.Nullable;

/**
 * Tests {@link MapTestSuiteBuilder} by using it against maps that have various negative behaviors.
 *
 * @author George van den Driessche
 */
@AndroidIncompatible // test-suite builders
public final class MapTestSuiteBuilderTests extends TestCase {
  private MapTestSuiteBuilderTests() {}

import java.util.Map.Entry;
import java.util.Set;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;

/**
 * Tests for {@link HashBiMap}.
 *
 * @author Mike Bostock
 */
@GwtCompatible
@NullMarked
public class HashBiMapTest extends TestCase {

  @J2ktIncompatible
  @AndroidIncompatible // test-suite builders

import java.util.Collections;
import java.util.List;
import java.util.Random;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for AbstractStreamingHasher.
 *
 * @author Dimitris Andreou
 */
@NullUnmarked
public class AbstractStreamingHasherTest extends TestCase {
  public void testBytes() {
    Sink sink = new Sink(4); // byte order insignificant here

import com.google.common.testing.NullPointerTester;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;

/**
 * Unit test for {@link Strings}.
 *
 * @author Kevin Bourrillion
 */
@NullMarked
@GwtCompatible
public class StringsTest extends TestCase {
  public void testNullToEmpty() {
    assertEquals("", Strings.nullToEmpty(null));