// won't happen
            }
        }

        if (listeners == null) {
            listeners = new ArrayList<>();

            if (logger.isDebugEnabled()) {
                listeners.add(new DebugResolutionListener(logger));
            }

            listeners.add(new WarningResolutionListener(logger));
        }

            Map<String, Artifact> managedVersions,
            ArtifactResolutionRequest repositoryRequest,
            ArtifactMetadataSource source,
            ArtifactFilter filter,
            List<ResolutionListener> listeners,
            List<ConflictResolver> conflictResolvers);

    ArtifactResolutionResult collect(
            Set<Artifact> artifacts,
            Artifact originatingArtifact,

        listener3.getPath() >> b.path

        when:
        graph.add(a)
        graph.addListener(listener1)
        graph.add(b)

        then:
        1 * listener1.onDiscovered(graph.root)
        1 * listener1.onDiscovered(a) >> { graph.addListener(listener2); false }
        1 * listener1.onDiscovered(b) >> { graph.addListener(listener3); false }
        1 * listener2.onDiscovered(b)

      return delegate;
    }

    @Override
    public void addListener(Runnable listener, Executor exec) {
      executionList.add(listener, exec);

      // When a listener is first added, we run a task that will wait for the delegate to finish,
      // and when it is done will run the listeners.
      if (hasListeners.compareAndSet(false, true)) {
        if (delegate.isDone()) {

		ConfigNamespace: "app",
	})

	listeners := s.Listeners(proxy)
	assertListEqual(t, xdstest.ExtractListenerNames(listeners), []string{
		"0.0.0.0_80",
		"virtualInbound",
		"virtualOutbound",
	})

	expectedEgressCluster := "outbound|5000|shiny|foo.bar"

	found := false
	for _, f := range xdstest.ExtractListener("virtualOutbound", listeners).FilterChains {

   * MoreExecutors#directExecutor}. Otherwise, avoid it: See the warnings on the docs for {@code
   * directExecutor}.
   *
   * <p>This is the most general listener interface. For common operations performed using
   * listeners, see {@link Futures}. For a simplified but general listener interface, see {@link
   * Futures#addCallback addCallback()}.
   *

   * MoreExecutors#directExecutor}. Otherwise, avoid it: See the warnings on the docs for {@code
   * directExecutor}.
   *
   * <p>This is the most general listener interface. For common operations performed using
   * listeners, see {@link Futures}. For a simplified but general listener interface, see {@link
   * Futures#addCallback addCallback()}.
   *

					IncrementEnvoyFilterMetric(lp.Key(), Listener, false)
					continue
				}
				// clone before append. Otherwise, subsequent operations on this listener will corrupt
				// the master value stored in CP.
				listeners = append(listeners, proto.Clone(lp.Value).(*listener.Listener))
				IncrementEnvoyFilterMetric(lp.Key(), Listener, true)
			}
		}
	}
	if listenersRemoved {

		// Prepend virtual inbound, as long as we are using redirection.
		listeners = append([]*listener.Listener{lb.inboundVirtualListener(virtualInboundFilterChains)}, listeners...)
	}

	return listeners
}

// inboundVirtualListener builds the virtual inbound listener.
func (lb *ListenerBuilder) inboundVirtualListener(chains []*listener.FilterChain) *listener.Listener {
	actualWildcards, _ := getWildcardsAndLocalHost(lb.node.GetIPMode())

   * across calls to multiple listeners. Specifically, a given listener will have its callbacks
   * invoked in the same order as the underlying service enters those states. Additionally, at most
   * one of the listener's callbacks will execute at once. However, multiple listeners' callbacks
   * may execute concurrently, and listeners may execute in an order different from the one in which
   * they were registered.