classPathFiles: List<File>,
    classPathDependencies: List<File> = emptyList(),
) : Closeable {

    private
    val relevantClassPathFiles = classPathFiles.filter { it.isDirectory || (it.isFile && it.length() > 0) }

    private
    val openJars = mutableMapOf<File, JarFile>()

    private

    File asciiFile = getTestFile("ascii.txt");
    File dir = asciiFile.getParentFile();
    assertTrue(Files.isDirectory().apply(dir));
    assertFalse(Files.isFile().apply(dir));

    assertFalse(Files.isDirectory().apply(asciiFile));
    assertTrue(Files.isFile().apply(asciiFile));
  }

  /** Returns a root path for the file system. */
  private static File root() {
    return File.listRoots()[0];
  }

            userSettingsFile = new File(commandLine.getOptionValue(CLIManager.ALTERNATE_USER_SETTINGS));
            userSettingsFile = resolveFile(userSettingsFile, workingDirectory);

            if (!userSettingsFile.isFile()) {
                throw new FileNotFoundException("The specified user settings file does not exist: " + userSettingsFile);
            }
        } else {
            userSettingsFile = DEFAULT_USER_SETTINGS_FILE;

        String path = getPathForLocalArtifact(request.getArtifact());
        File file = new File(getRepository().getBasedir(), path);

        LocalArtifactResult result = new LocalArtifactResult(request);
        if (file.isFile()) {
            result.setFile(file);
            result.setAvailable(true);
        }

        return result;
    }

    @Override

    }

    gradlebuild.docs.dsl.docbook.model.ClassDoc findClassDoc(String className) {
        gradlebuild.docs.dsl.docbook.model.ClassDoc classDoc = classes[className]
        if (classDoc == null && getFileForClass(className).isFile()) {
            return getClassDoc(className)
        }
        return classDoc
    }

    gradlebuild.docs.dsl.docbook.model.ClassDoc getClassDoc(String className) {

        String path = getPathForLocalArtifact(request.getArtifact());
        File file = new File(getRepository().getBasedir(), path);

        LocalArtifactResult result = new LocalArtifactResult(request);
        if (file.isFile()) {
            result.setFile(file);
            result.setAvailable(true);
        }

        return result;
    }

    @Override

        String path = getPathForLocalArtifact(request.getArtifact());
        File file = new File(getRepository().getBasedir(), path);

        LocalArtifactResult result = new LocalArtifactResult(request);
        if (file.isFile()) {
            result.setFile(file);
            result.setAvailable(true);
        }

        return result;
    }

    @Override

     */
    public ExtensionDescriptor build(File extensionJar) throws IOException {
        ExtensionDescriptor extensionDescriptor = null;

        if (extensionJar.isFile()) {
            try (JarFile pluginJar = new JarFile(extensionJar, false)) {
                ZipEntry pluginDescriptorEntry = pluginJar.getEntry(getExtensionDescriptorLocation());

    File asciiFile = getTestFile("ascii.txt");
    File dir = asciiFile.getParentFile();
    assertTrue(Files.isDirectory().apply(dir));
    assertFalse(Files.isFile().apply(dir));

    assertFalse(Files.isDirectory().apply(asciiFile));
    assertTrue(Files.isFile().apply(asciiFile));
  }

  /** Returns a root path for the file system. */
  private static File root() {
    return File.listRoots()[0];
  }

    return FilePredicate.IS_DIRECTORY;
  }

  /**
   * Returns a predicate that returns the result of {@link File#isFile} on input files.
   *
   * @since 15.0
   */
  public static Predicate<File> isFile() {
    return FilePredicate.IS_FILE;
  }

  private enum FilePredicate implements Predicate<File> {
    IS_DIRECTORY {
      @Override
      public boolean apply(File file) {