dispatcher.maxRequests = 2
    client.newCall(newRequest("http://a/1")).enqueue(callback)
    client.newCall(newRequest("http://b/1")).enqueue(callback)
    client.newCall(newRequest("http://c/1")).enqueue(callback)
    client.newCall(newRequest("http://a/2")).enqueue(callback)
    client.newCall(newRequest("http://b/2")).enqueue(callback)

    val dispatcherQueueStartC1 = eventRecorder.removeUpToEvent<DispatcherQueueStart>()

    boolean ran = false;
    @Nullable Callback callback = null;

    SimpleTearDown() {}

    SimpleTearDown(Callback callback) {
      this.callback = callback;
    }

    @Override
    public void tearDown() throws Exception {
      if (callback != null) {
        callback.run();
      }
      ran = true;
    }
  }

  private interface Callback {
    void run();
  }

        loadIncludes(path, sp, callback);
        substitute(sp, callback);
        sp.forEach(properties::setProperty);
    }

    public static void substitute(MavenProperties props, UnaryOperator<String> callback) {
        for (Enumeration<?> e = props.propertyNames(); e.hasMoreElements(); ) {
            String name = (String) e.nextElement();

        interpolate(properties, callback, null, true);
    }

    /**
     * Interpolates the values in the given map using the provided callback function.
     *
     * @param map The map containing key-value pairs to be interpolated.
     * @param callback The function to resolve variable values not found in the map.

			fchown(fd, uid, gid, callback) { callback(enosys()); },
			fstat(fd, callback) { callback(enosys()); },
			fsync(fd, callback) { callback(null); },
			ftruncate(fd, length, callback) { callback(enosys()); },
			lchown(path, uid, gid, callback) { callback(enosys()); },
			link(path, link, callback) { callback(enosys()); },
			lstat(path, callback) { callback(enosys()); },
			mkdir(path, perm, callback) { callback(enosys()); },

	return tx
}

// Update updates column with value using callbacks. Reference: https://gorm.io/docs/update.html#Update-Changed-Fields
func (db *DB) Update(column string, value interface{}) (tx *DB) {
	tx = db.getInstance()
	tx.Statement.Dest = map[string]interface{}{column: value}
	return tx.callbacks.Update().Execute(tx)
}

    MockCallback callback = new MockCallback("foo");
    addCallback(f, callback, directExecutor());
    f.set("foo");
  }

  public void testExecutorSuccess() {
    CountingSameThreadExecutor ex = new CountingSameThreadExecutor();
    SettableFuture<String> f = SettableFuture.create();
    MockCallback callback = new MockCallback("foo");
    Futures.addCallback(f, callback, ex);
    f.set("foo");

  private val source: BufferedSource,
  private val callback: Callback,
) {
  private var lastId: String? = null

  interface Callback {
    fun onEvent(
      id: String?,
      type: String?,
      data: String,
    )

    fun onRetryChange(timeMs: Long)
  }

  /**
   * Process the next event. This will result in a single call to [Callback.onEvent] *unless* the

@Implements(DnsResolver::class)
class ShadowDnsResolver {
  var responder: (Request) -> Unit = {
    it.callback.onAnswer(listOf(), 0)
  }

  data class Request(
    val network: Network?,
    val domain: String,
    val nsType: Int,
    val flags: Int,
    val callback: DnsResolver.Callback<List<InetAddress>>,
  )

  @Implementation
  fun query(
    network: Network?,
    domain: String,

    private final CoreExtensionEntry extension;
    private final UnaryOperator<String> callback;
    private final DefaultInterpolator interpolator = new DefaultInterpolator();

    public ExtensionConfigurationModule(CoreExtensionEntry extension, UnaryOperator<String> callback) {
        this.extension = extension;
        this.callback = callback;
    }

    @Override
    public void configure(Binder binder) {