return requireNonNull(DEST_TL.get());
  }

  /**
   * A thread-local destination buffer to keep us from creating new buffers. The starting size is
   * 1024 characters. If we grow past this we don't put it back in the threadlocal, we just keep
   * going and grow as needed.
   */
  private static final ThreadLocal<char[]> DEST_TL =
      new ThreadLocal<char[]>() {
        @Override
        protected char[] initialValue() {

  }

  /*
   * TODO(b/242884182): Figure out why this helps produce the same class file when we compile most
   * of common.collect a second time with the results of the first compilation on the classpath. Or
   * just back this out once we stop doing that (which we'll do after our internal GWT setup
   * changes).
   */
  @Override
  public ImmutableMap<Object, Collection<Object>> asMap() {
    return super.asMap();
  }

  }

  /**
   * Provides a check of whether an exception type is valid for use with {@link
   * FuturesGetChecked#getChecked(Future, Class)}, possibly using caching.
   *
   * <p>Uses reflection to gracefully fall back to when certain implementations aren't available.
   */
  @VisibleForTesting
  static class GetCheckedTypeValidatorHolder {
    static final GetCheckedTypeValidator BEST_VALIDATOR = getBestValidator();

 *
 * @author Sverre Sundsdal
 */
public class MinMaxPriorityQueueBenchmark {
  @Param private ComparatorType comparator;

  // TODO(kevinb): add 1000000 back when we have the ability to throw
  // NotApplicableException in the expensive comparator case.
  @Param({"100", "10000"})
  private int size;

  @Param private HeapType heap;

  private Queue<Integer> queue;

   * Finalizer directly with no problems.
   *
   * If this library is loaded in an application class loader, it's important that Finalizer not
   * have a strong reference back to the class loader. Otherwise, you could have a graph like this:
   *
   * Finalizer Thread runs instance of -> Finalizer.class loaded by -> Application class loader

   * Finalizer directly with no problems.
   *
   * If this library is loaded in an application class loader, it's important that Finalizer not
   * have a strong reference back to the class loader. Otherwise, you could have a graph like this:
   *
   * Finalizer Thread runs instance of -> Finalizer.class loaded by -> Application class loader

        testDir = testFile.getParentFile(); // the testdata directory
      } catch (Exception ignore) {
        // probably URISyntaxException or IllegalArgumentException
        // fall back to copying URLs to files in the testDir == null block below
      }
    }

    if (testDir == null) {
      // testdata resources aren't file:// urls, so create a directory to store them in and then

   * Multimap#asMap()} will iterate through the keys in the order that they were first added to the
   * multimap, save that if all values associated with a key are removed and then the key is added
   * back into the multimap, that key will come last in the key iteration order.
   */
  public static MultimapBuilderWithKeys<@Nullable Object> linkedHashKeys() {
    return linkedHashKeys(DEFAULT_EXPECTED_KEYS);
  }

  /**

    try {
      return Thread.class.getConstructor(
          ThreadGroup.class, Runnable.class, String.class, long.class, boolean.class);
    } catch (Throwable t) {
      // Probably pre Java 9. We'll fall back to Thread.inheritableThreadLocals.
      return null;
    }
  }

 * using a lock, however it is dangerous to dispatch listeners while holding a lock because they
 * might run on the {@code directExecutor()} or be otherwise re-entrant (call back into your
 * object). So it is important to not call {@link #dispatch} while holding any locks. This is why
 * {@link #enqueue} and {@link #dispatch} are 2 different methods. It is expected that the decision