import java.util.logging.Level;
import java.util.logging.Logger;
import org.jspecify.annotations.NullMarked;

/**
 * A {@code TearDownStack} contains a stack of {@link TearDown} instances.
 *
 * <p>This class is thread-safe.
 *
 * @author Kevin Bourrillion
 * @since 10.0
 */
@GwtCompatible
@NullMarked
public class TearDownStack implements TearDownAccepter {

import java.util.logging.Level;
import java.util.logging.Logger;
import org.jspecify.annotations.NullMarked;

/**
 * A {@code TearDownStack} contains a stack of {@link TearDown} instances.
 *
 * <p>This class is thread-safe.
 *
 * @author Kevin Bourrillion
 * @since 10.0
 */
@GwtCompatible
@NullMarked
public class TearDownStack implements TearDownAccepter {

    /**
     * Flag indicating whether thumbnail generation is currently in progress.
     */
    protected volatile boolean generating;

    private Thread thumbnailQueueThread;

    /**
     * Size of the thumbnail path cache.
     */
    protected int thumbnailPathCacheSize = 10;

    /**
     * File extension for generated thumbnail images.
     */

    cache.getUnchecked("a");
    shouldWait.set(true);

    CountDownLatch computationStarted = new CountDownLatch(1);
    CountDownLatch computationComplete = new CountDownLatch(1);
    new Thread(
            () -> {
              computationStarted.countDown();
              cache.getUnchecked("b");
              computationComplete.countDown();
            })
        .start();

    cache.getUnchecked("a");
    shouldWait.set(true);

    CountDownLatch computationStarted = new CountDownLatch(1);
    CountDownLatch computationComplete = new CountDownLatch(1);
    new Thread(
            () -> {
              computationStarted.countDown();
              cache.getUnchecked("b");
              computationComplete.countDown();
            })
        .start();

        try (InputStream is = getClass().getClassLoader().getResourceAsStream("../webapp/WEB-INF/web.xml")) {
            if (is == null) {
                try (InputStream is2 = Thread.currentThread().getContextClassLoader().getResourceAsStream("web.xml")) {
                    if (is2 != null) {
                        webXmlDocument = builder.parse(is2);
                    }
                }

/**
 * A record representing the result of a single request operation, containing the original request,
 * the result (if successful), and any error that occurred during processing.
 * <p>
 * This class is immutable and thread-safe, suitable for use in concurrent operations.
 *
 * @param <REQ> The type of the request
 * @param <REP> The type of the response, which must extend {@code Result<REQ>}
 * @param request The original request that was processed

        .build()
    val request = Request(server.url("/"))
    val response1 = client.newCall(request).execute()
    assertThat(response1.body.string()).isEqualTo("a")

    // Give the thread pool a chance to evict.
    Thread.sleep(500)
    val response2 = client.newCall(request).execute()
    assertThat(response2.body.string()).isEqualTo("b")
    assertThat(server.takeRequest().exchangeIndex).isEqualTo(0)

   * Futures#addCallback addCallback()}.
   *
   * <p>Memory consistency effects: Actions in a thread prior to adding a listener <a
   * href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-17.html#jls-17.4.5">
   * <i>happen-before</i></a> its execution begins, perhaps in another thread.
   *
   * <p>Guava implementations of {@code ListenableFuture} promptly release references to listeners

 * contract.
 *
 * <p>The {@code standard} methods and the collection views they return are not guaranteed to be
 * thread-safe, even when all of the methods that they depend on are thread-safe.
 *
 * @author Louis Wasserman
 * @since 12.0
 */
@GwtIncompatible
public abstract class ForwardingNavigableSet<E extends @Nullable Object>