@Throws(IOException::class)
  fun peekTrailers(): Headers?

  /**
   * Cancel this stream. Resources held by this stream will be cleaned up, though not synchronously.
   * That may happen later by the connection pool thread.
   */
  fun cancel()

  /**
   * Carries an exchange. This is usually a connection, but it could also be a connect plan for
   * CONNECT tunnels. Note that CONNECT tunnels are significantly less capable than connections.

 *
 * <p>One {@code Type} is visited at most once. The second time the same type is visited, it's
 * ignored by {@link #visit}. This avoids infinite recursion caused by recursive type bounds.
 *
 * <p>This class is not thread safe.
 *
 * @author Ben Yu
 */
abstract class TypeVisitor {

  private final Set<Type> visited = new HashSet<>();

  /**

    override fun writeTo(sink: BufferedSink) {
      try {
        var i = 0
        while (i < contentLength()) {
          sink.write(chunk!!)
          sink.flush()
          Thread.sleep(100)
          i += chunk.size
        }
      } catch (e: IOException) {
        ioe = e
      } catch (e: InterruptedException) {
        throw RuntimeException(e)
      }
    }
  }

     */
    protected void loadProtocols(final String basePackage) {
        final List<String> subPackages = new ArrayList<>();
        final String path = basePackage.replace('.', '/');
        final ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
        try {
            final Enumeration<URL> resources = classLoader.getResources(path);

            while (resources.hasMoreElements()) {

    assertThat(recordedRequest.url.encodedQuery).isEqualTo(
      "ct&dns=AAABAAABAAAAAAAABmdvb2dsZQNjb20AAAEAAQ",
    )

    assertThat(cacheEvents()).containsExactly("CacheMiss")

    Thread.sleep(2000)
    server.enqueue(
      dnsResponse(
        "0000818000010003000000000567726170680866616365626f6f6b03636f6d0000010001c00c000500010" +

            return new Metadata(new MetadataStaxReader().read(in, false));
        } catch (FileNotFoundException e) {
            throw new RepositoryMetadataReadException("Cannot read metadata from '" + mappingFile + "'", e);
        } catch (IOException | XMLStreamException e) {
            throw new RepositoryMetadataReadException(
                    "Cannot read metadata from '" + mappingFile + "': " + e.getMessage(), e);
        }

          }
          buffer.add(e);
          added++;
        }
      }
    } finally {
      if (interrupted) {
        Thread.currentThread().interrupt();
      }
    }
    return added;
  }

  /**
   * Returns a synchronized (thread-safe) queue backed by the specified queue. In order to guarantee
   * serial access, it is critical that <b>all</b> access to the backing queue is accomplished

    private final java.util.concurrent.ScheduledExecutorService rotationScheduler =
            java.util.concurrent.Executors.newSingleThreadScheduledExecutor(r -> {
                Thread t = new Thread(r, "SecureKeyManager-Rotation");
                t.setDaemon(true);
                return t;
            });
    private java.util.concurrent.ScheduledFuture<?> rotationTask;

    /**

import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Basher test for {@link ConcurrentHashMultiset}: start a bunch of threads, have each of them do
 * operations at random. Each thread keeps track of the per-key deltas that it's directly
 * responsible for; after all threads have completed, we sum the per-key deltas and compare to the
 * existing multiset values.
 *
 * @author mike nonemacher
 */

@NullUnmarked

     * implementations, supports add() under JDK8. This seems problematic, but I
     * didn't see that discussed in the review, which included many other
     * changes: https://mail.openjdk.org/pipermail/core-libs-dev/2013-May/thread.html#17367
     *
     * TODO(cpovirk): decide what the best long-term action here is: force users
     * to suppress (as we do now), stop testing entrySet().add() at all, make