-->

#### Special notes for your reviewer:

#### Does this PR introduce a user-facing change?
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    return method.getAnnotation(AllowConcurrentEvents.class) != null;
  }

  /**
   * Subscriber that synchronizes invocations of a method to ensure that only one thread may enter
   * the method at a time.
   */
  @VisibleForTesting
  static final class SynchronizedSubscriber extends Subscriber {

    private SynchronizedSubscriber(EventBus bus, Object target, Method method) {

    eventListener.canceled(this)
  }

  override fun isCanceled(): Boolean = canceled

  override fun execute(): Response {
    check(executed.compareAndSet(false, true)) { "Already Executed" }

    timeout.enter()
    callStart()
    try {
      client.dispatcher.executed(this)
      return getResponseWithInterceptorChain()
    } finally {
      client.dispatcher.finished(this)
    }
  }

      } catch (ClassNotFoundException runningUnderAndroidOrJava8) {
        /*
         * I'm not sure that we could actually get here for *Android*: I would expect us to enter
         * the POSIX code path instead. And if we tried this code path, we'd have trouble unless we
         * were running under a new enough version of Android to support NIO.
         *

    if (approxCmp > 0) {
      /*
       * The code is written so that even completely incorrect approximations will still yield the
       * correct answer eventually, but in practice this branch should almost never be entered, and
       * even then the loop should not run more than once.
       */
      do {
        approxLog10--;
        approxPow = approxPow.divide(BigInteger.TEN);
        approxCmp = approxPow.compareTo(x);

 * which is commonly used for Kerberos-based authentication in Windows environments.
 * It handles the negotiation between client and server to establish a secure
 * authentication context without requiring users to explicitly enter credentials.
 *
 * The authenticator supports various configuration options including delegation,
 * basic authentication fallback, and localhost authentication bypass.
 */

        columnIterator = rowEntry.getValue().entrySet().iterator();
      }
      /*
       * requireNonNull is safe because:
       *
       * - columnIterator started off pointing to an empty iterator, so we must have entered the
       *   `if` body above at least once. Thus, if we got this far, that `if` body initialized
       *   rowEntry at least once.
       *

           * load our class directly (which would trigger non-reflective loading of VarHandle) from
           * within a `try` block, then an error might be thrown even before we enter the `try`
           * block: https://github.com/google/truth/issues/333#issuecomment-765652454
           *
           * Also, it's nice that this approach should let us catch *only* ClassNotFoundException

          currentKey = entry.getKey();
          valueItr = entry.getValue().iterator();
        }
        /*
         * requireNonNull is safe: The first call to this method always enters the !hasNext() case
         * and populates currentKey, after which it's never cleared.
         */
        return immutableEntry(requireNonNull(currentKey), valueItr.next());
      }
    };
  }

        collection = mapEntry.getValue();
        valueIterator = collection.iterator();
      }
      /*
       * uncheckedCastNullableTToT is safe: The first call to this method always enters the !hasNext() case and
       * populates key, after which it's never cleared.
       */
      return output(uncheckedCastNullableTToT(key), valueIterator.next());
    }

    @Override