.put(GenericDeclaration.class, Object.class)
          .put(Type.class, Object.class)
          .build();

  /**
   * type → implementation. Inherently mutable interfaces and abstract classes are mapped to their
   * default implementations and are "new"d upon get().
   */
  private static final ConcurrentMap<Class<?>, Class<?>> implementations = Maps.newConcurrentMap();

import java.util.concurrent.atomic.AtomicReference;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;

/**
 * Base class for JSR166 Junit TCK tests. Defines some constants, utility methods and classes, as
 * well as a simple framework for helping to make sure that assertions failing in generated threads
 * cause the associated test that generated them to itself fail (which JUnit does not otherwise

      assertThat(resource.getResourceName()).doesNotContain("com/google/common/reflect/");
    }
  }

  private static ClassPath.ClassInfo findClass(
      Iterable<ClassPath.ClassInfo> classes, Class<?> cls) {
    for (ClassPath.ClassInfo classInfo : classes) {
      if (classInfo.getName().equals(cls.getName())) {
        return classInfo;
      }
    }
    throw new AssertionError("failed to find " + cls);
  }

 *   <li><b>Integrity.</b> This type cannot be subclassed outside this package (which would allow
 *       these guarantees to be violated).
 * </ul>
 *
 * <h4>"Interfaces", not implementations</h4>
 *
 * <p>These are classes instead of interfaces to prevent external subtyping, but should be thought
 * of as interfaces in every important sense. Each public class such as {@link ImmutableSet} is a

   * add(Object)} call will throw a {@code ClassCastException}.
   *
   * <p>The type specification is {@code <E extends Comparable>}, instead of the more specific
   * {@code <E extends Comparable<? super E>>}, to support classes defined without generics.
   */
  @SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989
  public static <E extends Comparable> TreeMultiset<E> create() {
    return new TreeMultiset<>(Ordering.natural());

 * object.
 *
 * <p><b>Comparison to {@code java.util.Optional} (JDK 8 and higher):</b> A new {@code Optional}
 * class was added for Java 8. The two classes are extremely similar, but incompatible (they cannot
 * share a common supertype). <i>All</i> known differences are listed either here or with the
 * relevant methods below.
 *
 * <ul>

   * compares, using {@link #compare(byte, byte)}), the first pair of values that follow any common
   * prefix, or when one array is a prefix of the other, treats the shorter array as the lesser. For
   * example, {@code [] < [0x01] < [0x01, 0x7F] < [0x01, 0x80] < [0x02]}. Values are treated as
   * unsigned.
   *
   * <p>The returned comparator is inconsistent with {@link Object#equals(Object)} (since arrays

  Object writeReplace() {
    return super.writeReplace();
  }

  // This class is never actually serialized directly, but we have to make the
  // warning go away (and suppressing would suppress for all nested classes too)
  @J2ktIncompatible // serialization
  private static final long serialVersionUID = 0;

        elapsedMillis + 5 >= expectedMillis);
  }

  // TODO(cpovirk): Split this into separate CountDownLatch and IncrementableCountDownLatch classes.

  /** Manages a {@link BlockingQueue} and associated timings for a {@code put} call. */
  private static final class TimedPutQueue {
    final BlockingQueue<String> queue;
    final Completion completed;

 *   <li>Next, non-null {@code Foo} values are passed to {@code getBarFunction} (we will be
 *       comparing {@code Bar} values from now on)
 *   <li>Next, if only one {@code Bar} is null, that null value is treated as <i>lesser</i>
 *   <li>Finally, natural ordering is used (i.e. the result of {@code Bar.compareTo(Bar)} is
 *       returned)
 * </ol>
 *