throw new IllegalArgumentException("Invalid threads core multiplier value: '" + threadConfiguration
                            + "'. Value must be positive.");
                }

                int procs = Runtime.getRuntime().availableProcessors();
                int threads = (int) (coreMultiplier * procs);
                return threads == 0 ? 1 : threads;
            } else {

 * equality for both keys and values, unlike {@code ForwardingMap}.
 *
 * <p>The {@code standard} methods and the collection views they return are not guaranteed to be
 * thread-safe, even when all of the methods that they depend on are thread-safe.
 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
/*

    val atomicTags = AtomicReference<Tags>(tags)
    val result =
      atomicTags.computeIfAbsent(String::class) {
        // 'Race' by making another computeIfAbsent call. In practice this would be another thread.
        assertThat(atomicTags.computeIfAbsent(Integer::class) { 5 as Integer }).isEqualTo(5)
        "a"
      }
    assertThat(result).isEqualTo("a")
    assertThat(atomicTags.get()[String::class]).isEqualTo("a")

    assertThat(inputStream.read()).isEqualTo('A'.code)
    assertThat(inputStream.read()).isEqualTo('B'.code)
    assertThat(inputStream.read()).isEqualTo('C'.code)
    assertThat(inputStream.read()).isEqualTo('D'.code)
    assertThat(inputStream.read()).isEqualTo('E'.code)
    assertThat(inputStream.read()).isEqualTo('F'.code)
    assertThat(inputStream.read()).isEqualTo(-1)

 * instances is using {@link CacheBuilder}.
 *
 * <p>Implementations of this interface are expected to be thread-safe, and can be safely accessed
 * by multiple concurrent threads.
 *
 * <p>When evaluated as a {@link Function}, a cache yields the same result as invoking {@link
 * #getUnchecked}.
 *

    void recordHits(int count);

    /**
     * Records cache misses. This should be called when a cache request returns a value that was not
     * found in the cache. This method should be called by the loading thread, as well as by threads
     * blocking on the load. Multiple concurrent calls to {@link Cache} lookup methods with the same
     * key on an absent value should result in a single call to either {@code recordLoadSuccess} or

 * methods that they depend on are thread-safe.
 *
 * @author Kevin Bourrillion
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingSet<E extends @Nullable Object> extends ForwardingCollection<E>
    implements Set<E> {
  // TODO(lowasser): identify places where thread safety is actually lost

    private List<File> filesToDelete = new ArrayList<>();

    private final String baseFilename;

    private final String fileSuffix;

    private StackTraceElement callerInfo;

    private Thread cleanupWarning;

    private boolean warnAboutCleanup = false;

    public TestFileManager(String baseFilename, String fileSuffix) {
        this.baseFilename = baseFilename;
        this.fileSuffix = fileSuffix;

@J2ktIncompatible
@GwtIncompatible
public interface FinalizableReference {
  /**
   * Invoked on a background thread after the referent has been garbage collected unless security
   * restrictions prevented starting a background thread, in which case this method is invoked when
   * new references are created.
   */
  void finalizeReferent();

 *
 * <p>Note that although your APIs should be liberal in what they accept, your methods which
 * <i>return</i> iterables should make every attempt to return ones of the robust variety.
 *
 * <p>This testing utility is not thread-safe.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
public final class MinimalIterable<E extends @Nullable Object> implements Iterable<E> {