* Example usage:
     * </p>
     * <pre>
     * Path baseDir = Paths.get("/var/app/data");
     * Path userPath = Paths.get(userInput);
     * if (!FileUtil.isPathSafe(userPath, baseDir)) {
     *     throw new SecurityException("Path traversal attempt detected");
     * }
     * </pre>
     *
     * @param pathToCheck the path to validate (must not be {@literal null})

     *
     * @return an Unsafe instance if successful
     */
    private static Unsafe getUnsafe() {
      try {
        return Unsafe.getUnsafe();
      } catch (SecurityException tryReflectionInstead) {
        // We'll try reflection instead.
      }
      try {
        return AccessController.doPrivileged(
            (PrivilegedExceptionAction<Unsafe>)
                () -> {

   * to Unsafe.getUnsafe when integrating into a jdk.
   *
   * @return a sun.misc.Unsafe
   */
  private static Unsafe getUnsafe() {
    try {
      return Unsafe.getUnsafe();
    } catch (SecurityException tryReflectionInstead) {
    }
    try {
      return AccessController.doPrivileged(
          new PrivilegedExceptionAction<Unsafe>() {
            @Override
            public Unsafe run() throws Exception {

          return OFFSET_UNSAFE_APPROACH_IS_UNAVAILABLE;
        }
      }

      private static @Nullable Unsafe getUnsafe() {
        try {
          return Unsafe.getUnsafe();
        } catch (SecurityException e) {
          // that's okay; try reflection instead
        }
        try {
          return doPrivileged(
              (PrivilegedExceptionAction<Unsafe>)
                  () -> {

  val proxy: Proxy? = builder.proxy

  @get:JvmName("proxySelector")
  val proxySelector: ProxySelector =
    when {
      // Defer calls to ProxySelector.getDefault() because it can throw a SecurityException.
      builder.proxy != null -> NullProxySelector

      else -> builder.proxySelector ?: ProxySelector.getDefault() ?: NullProxySelector
    }

  @get:JvmName("proxyAuthenticator")

    // TODO(b/139726489): Confirm that null is impossible here.
    Thread result = requireNonNull(platformThreadFactory().newThread(runnable));
    try {
      result.setName(name);
    } catch (SecurityException e) {
      // OK if we can't set the name in this environment.
    }
    return result;
  }

  // TODO(lukes): provide overloads for ListeningExecutorService? ListeningScheduledExecutorService?