ThumbnailManager mockThumbnailManager = new ThumbnailManager() {
                private int callCount = 0;

                @Override
                public int generate(ExecutorService executorService, boolean cleanup) {
                    // Return 0 to exit the loop
                    if (callCount++ == 0) {
                        return 1;
                    }
                    return 0;

import java.util.concurrent.Delayed;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.ThreadPoolExecutor.CallerRunsPolicy;
import java.util.concurrent.TimeUnit;

/**
 * Factory methods for {@link ExecutorService} for testing.
 *
 * @author Chris Nokleberg
 * @since 14.0
 */
@GwtIncompatible

import com.google.common.util.concurrent.ListenableFuture;
import java.util.concurrent.CancellationException;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import junit.framework.TestCase;
import org.jspecify.annotations.Nullable;

/**

import com.google.common.util.concurrent.ListenableFuture;
import java.util.concurrent.CancellationException;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import junit.framework.TestCase;
import org.jspecify.annotations.Nullable;

/**

    ExecutorService delegate =
        new ThreadPoolExecutor(0, Integer.MAX_VALUE, 60, SECONDS, new SynchronousQueue<>()) {
          @Override
          public void close() {
            throw new AssertionError(
                "ForwardingExecutorService should have used the default method"
                    + " ExecutorService.close() (which would forward to methods like shutdown() on"

        }
    }

    @Override
    @PreDestroy
    public void close() throws Exception {
        if (executorService != null) {
            try {
                executorService.shutdown();
                executorService.awaitTermination(60, TimeUnit.SECONDS);
            } catch (final InterruptedException e) {
                if (logger.isDebugEnabled()) {

  @RegisterExtension
  var platform = PlatformRule()

  private lateinit var executorService: ExecutorService

  private var serverSocket: ServerSocket? = null

  @BeforeEach fun setUp() {
    executorService = Executors.newCachedThreadPool(threadFactory("HandshakeCertificatesTest"))
  }

  @AfterEach fun tearDown() {
    executorService.shutdown()
    serverSocket?.closeQuietly()
  }

  @Test fun clientAndServer() {

      }
    }
  }

  /**
   * Invokes {@code executor.}{@link ExecutorService#awaitTermination(long, TimeUnit)
   * awaitTermination(long, TimeUnit)} uninterruptibly with no timeout.
   *
   * @since 30.0
   */
  @J2ktIncompatible
  @GwtIncompatible // concurrency
  public static void awaitTerminationUninterruptibly(ExecutorService executor) {

import com.google.common.collect.Multiset;
import com.google.common.testing.TestLogHandler;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.logging.Level;
import java.util.logging.Logger;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/** Tests for {@link ListenerCallQueue}. */
@NullUnmarked

import com.google.common.collect.Multiset;
import com.google.common.testing.TestLogHandler;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.logging.Level;
import java.util.logging.Logger;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/** Tests for {@link ListenerCallQueue}. */
@NullUnmarked