Files.createDirectory(specialDir);
        Files.writeString(specialDir.resolve("file with spaces.txt"), "spaces");
        Files.writeString(specialDir.resolve("file-with-dashes.txt"), "dashes");
        Files.writeString(specialDir.resolve("file_with_underscores.txt"), "underscores");
        Files.writeString(specialDir.resolve("file.multiple.dots.txt"), "dots");

    }

  /**
   * Returns an OkHttpClient for tests to use as a starting point.
   *
   * The returned client installs a default event listener that gathers debug information. This will
   * be logged if the test fails.
   *
   * This client is also configured to be slightly more deterministic, returning a single IP

      new RegularImmutableSet<>(EMPTY_ARRAY, 0, EMPTY_ARRAY, 0);

  private final transient Object[] elements;
  private final transient int hashCode;
  // the same values as `elements` in hashed positions (plus nulls)
  @VisibleForTesting final transient @Nullable Object[] table;
  // 'and' with an int to get a valid table index.
  private final transient int mask;

/**
 * This is an implementation of the HMACT64 keyed hashing algorithm.
 * HMACT64 is defined by Luke Leighton as a modified HMAC-MD5 (RFC 2104)
 * in which the key is truncated at 64 bytes (rather than being hashed
 * via MD5).
 */
public class HMACT64 extends MessageDigest implements Cloneable {

    private static final int BLOCK_LENGTH = 64;

    private static final byte IPAD = (byte) 0x36;

/**
 * This is an implementation of the HMACT64 keyed hashing algorithm.
 * HMACT64 is defined by Luke Leighton as a modified HMAC-MD5 (RFC 2104)
 * in which the key is truncated at 64 bytes (rather than being hashed
 * via MD5).
 */
class HMACT64 extends MessageDigest implements Cloneable {

    private static final int BLOCK_LENGTH = 64;

    private static final byte IPAD = (byte) 0x36;

    private static final int DEFAULT_HASH_ALGORITHM = HASH_ALGO_SHA512;
    private static final int SALT_SIZE = 32; // 32 bytes as per SMB 3.1.1 spec
    private static final int HASH_SIZE_SHA512 = 64; // SHA-512 produces 64-byte hashes

    // Session-specific preauth integrity contexts
    private final ConcurrentMap<String, PreauthIntegrityContext> sessionContexts = new ConcurrentHashMap<>();

    // Security configuration

  }

  private void assertEvents(String... events) {
    assertEquals(Arrays.toString(events), stopwatch.readEventsAndClear());
  }

  /**
   * The stopwatch gathers events and presents them as strings. R0.6 means a delay of 0.6 seconds
   * caused by the (R)ateLimiter U1.0 means the (U)ser caused the stopwatch to sleep for a second.
   */

  }

  private void assertEvents(String... events) {
    assertEquals(Arrays.toString(events), stopwatch.readEventsAndClear());
  }

  /**
   * The stopwatch gathers events and presents them as strings. R0.6 means a delay of 0.6 seconds
   * caused by the (R)ateLimiter U1.0 means the (U)ser caused the stopwatch to sleep for a second.
   */

trusts the certificate authorities of the host platform. This strategy maximizes connectivity, but it is subject to certificate authority attacks such as the [2011 DigiNotar attack](https://www.computerworld.com/article/2510951/cybercrime-hacking/hackers-spied-on-300-000-iranians-using-fake-google-certificate.html). It also assumes your HTTPS servers’ certificates are signed by a certificate authority.

Use [CertificatePinner](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-certificate-pinner/)...

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.atomic.AtomicInteger;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Basher test for {@link ConcurrentHashMultiset}: start a bunch of threads, have each of them do
 * operations at random. Each thread keeps track of the per-key deltas that it's directly