}

            seen = true;

            tg = aTgList;
            Thread[] ts = new Thread[tg.activeCount()];
            tg.enumerate(ts);

            for (Thread active : ts) {
                String name = active.getName();
                boolean daemon = active.isDaemon();
                assertTrue(daemon, name + " is no daemon Thread.");
            }
        }

/**
 * A {@link TransferListener} implementation that wraps another delegate {@link TransferListener} but makes it run
 * on single thread, keeping the listener logic simple. This listener also blocks on last transfer event to allow
 * output to perform possible cleanup. It spawns a daemon thread to consume queued events that may fall in even
 * concurrently.
 *
 * @since 4.0.0
 */

        // for technical reasons we cannot throw here, even if delegate does cancel transfer
        listener.transferInitiated(event(session, resource, TransferEvent.EventType.INITIATED));

        Thread.sleep(500); // to make sure queue is processed, cancellation applied

        // subsequent call will cancel
        assertThrows(
                TransferCancelledException.class,

        }

        ClassLoader oldClassLoader = Thread.currentThread().getContextClassLoader();
        try {
            Thread.currentThread().setContextClassLoader(pluginDescriptor.getClassRealm());

            return container.lookup(role, roleHint);
        } finally {
            Thread.currentThread().setContextClassLoader(oldClassLoader);
        }
    }

        ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
        try {
            for (AbstractMavenLifecycleParticipant listener :
                    getExtensionComponents(session.getProjects(), AbstractMavenLifecycleParticipant.class)) {
                Thread.currentThread().setContextClassLoader(listener.getClass().getClassLoader());

            }
        });

        ClassLoader oldCL = Thread.currentThread().getContextClassLoader();
        try {
            container.setLookupRealm(null);
            container.setLoggerManager(createLoggerManager());
            container.getLoggerManager().setThresholds(toPlexusLoggingLevel(context.loggerLevel));
            Thread.currentThread().setContextClassLoader(container.getContainerRealm());

    private final Executor executor;

    public DefaultArtifactResolver() {
        int threads = Integer.getInteger("maven.artifact.threads", 5);
        if (threads <= 1) {
            executor = Runnable::run;
        } else {
            executor = new ThreadPoolExecutor(
                    threads, threads, 3, TimeUnit.SECONDS, new LinkedBlockingQueue<>(), new DaemonThreadCreator());
        }
    }

        this.session = session;
        this.project = project;
        ClassLoader ttcl = Thread.currentThread().getContextClassLoader();
        try {
            Thread.currentThread().setContextClassLoader(project.getClassRealm());
            this.packaging = session.requirePackaging(project.getPackaging());
        } finally {
            Thread.currentThread().setContextClassLoader(ttcl);
        }
    }

    private List<File> filesToDelete = new ArrayList<>();

    private final String baseFilename;

    private final String fileSuffix;

    private StackTraceElement callerInfo;

    private Thread cleanupWarning;

    private boolean warnAboutCleanup = false;

    public TestFileManager(String baseFilename, String fileSuffix) {
        this.baseFilename = baseFilename;
        this.fileSuffix = fileSuffix;

    @Override
    public Lookup getLookup() {
        return lookup;
    }

    @Override
    public void close() {
        try {
            plexusContainer.dispose();
        } finally {
            Thread.currentThread().setContextClassLoader(previousClassLoader);
        }
    }