*
 * <p>This class ensures that the temporary file is deleted if it is not needed.
 * It uses a logger to log warnings if there are issues deleting the temporary file.</p>
 *
 * <p>Fields:</p>
 * <ul>
 *   <li>{@code logger} - Logger instance for logging warnings.</li>
 *   <li>{@code PREFIX} - Prefix for the temporary file name.</li>
 *   <li>{@code SUFFIX} - Suffix for the temporary file name.</li>

   * relying on this, as we have made incompatible changes to serialized forms in the past and
   * expect to do so again, as discussed in https://github.com/google/guava#important-warnings.
   */
  @SuppressWarnings("unused")
  private static final class SerializedForm<V> implements Serializable {
    final ImmutableMap<?, V> map;

    SerializedForm(ImmutableMap<?, V> map) {

    dependsOn(compileKotlinTask)

    if (enableValidation) {
      compileKotlinTask.source(file("src/main/java9"))
    }

    // Ignore warnings about using 'requires transitive' on automatic modules.
    // not needed when compiling with recent JDKs, e.g. 17
    options.compilerArgs.add("-Xlint:-requires-transitive-automatic")

   * }
   *
   * <p>When selecting an executor, note that {@code directExecutor} is dangerous in some cases. See
   * the discussion in the {@link #addListener} documentation. All its warnings about heavyweight
   * listeners are also applicable to heavyweight functions passed to this method.
   *
   * <p>This method is similar to {@link java.util.concurrent.CompletableFuture#exceptionally}. It

-   [guava-discuss: For open-ended questions and discussion](https://groups.google.com/group/guava-discuss)

## IMPORTANT WARNINGS

1. APIs marked with the `@Beta` annotation at the class or method level
are subject to change. They can be modified in any way, or even
removed, at any time. If your code is a library itself (i.e. it is

              restoreInterruptIfIsInterruptedException(e);
              logger.get().log(WARNING, "thrown by close()", e);
            }
          });
    } catch (RejectedExecutionException e) {
      if (logger.get().isLoggable(WARNING)) {
        logger
            .get()
            .log(
                WARNING,
                String.format("while submitting close to %s; will close inline", executor),

    return t;
  }

  /** Returns {@code null} as any type, even one that does not include {@code null}. */
  @SuppressWarnings({"nullness", "TypeParameterUnusedInFormals", "ReturnMissingNullable"})
  // The warnings are legitimate. Each time we use this method, we document why.
  @ParametricNullness
  static <T extends @Nullable Object> T unsafeNull() {
    return null;
  }

  private NullnessCasts() {}

    return t;
  }

  /** Returns {@code null} as any type, even one that does not include {@code null}. */
  @SuppressWarnings({"nullness", "TypeParameterUnusedInFormals", "ReturnMissingNullable"})
  // The warnings are legitimate. Each time we use this method, we document why.
  @ParametricNullness
  static <T extends @Nullable Object> T unsafeNull() {
    return null;
  }

  private NullnessCasts() {}

        }
        return themeName;
    }

    /**
     * Recursively deletes a directory and all its contents.
     * Does not throw exceptions, only logs warnings if deletion fails.
     *
     * @param dir the directory to delete
     */
    protected void closeQuietly(final Path dir) {
        if (Files.notExists(dir)) {
            if (logger.isDebugEnabled()) {

     * flexibility, and debug mode warnings are enabled when debug logging is active.
     * </p>
     */
    public DataSerializer() {
        kryoThreadLocal = ThreadLocal.withInitial(() -> {
            final Kryo kryo = new Kryo();
            // TODO use kryo.register for security
            // SECURITY WARNING: setRegistrationRequired(false) allows deserialization of arbitrary classes