* Returns the path to an alternate POM file.
     *
     * @return an {@link Optional} containing the path to the alternate POM file, or empty if not specified
     */
    @Nonnull
    Optional<String> alternatePomFile();

    /**
     * Indicates whether Maven should operate in offline mode.
     *
     * @return an {@link Optional} containing true if offline mode is enabled, false if disabled, or empty if not specified
     */

     * Gets the one-based index of the line containing the error.
     *
     * @return The one-based index of the line containing the error or a non-positive value if unknown.
     */
    public int getLineNumber() {
        return lineNumber;
    }

    /**
     * Gets the one-based index of the column containing the error.
     *
     * @return The one-based index of the column containing the error or non-positive value if unknown.

    /**
     * Gets the one-based index of the line containing the problem. The line number should refer to some text file that
     * is given by {@link #getSource()}.
     *
     * @return The one-based index of the line containing the problem or a non-positive value if unknown.
     */
    int getLineNumber();

    /**
     * Gets the one-based index of the column containing the problem. The column number should refer to some text file

     *
     * @return an {@link Optional} containing the map of user properties, or empty if not set
     */
    @Nonnull
    Optional<Map<String, String>> userProperties();

    /**
     * Indicates whether to show the version information and exit.
     *
     * @return an {@link Optional} containing the boolean flag, or empty if not set
     */
    @Nonnull

   per project settings can be defined by files in <<<.mvn/>>> directory:

   * <<<.mvn/jvm.config>>> containing jvm options,

   * <<<.mvn/maven.config>>> containing Maven command-line parameter,

   * <<<.mvn/extensions.xml>>> containing {{{./core-extensions.html}a list of extensions}},

 * since 3.5.0, output is colorized by default, with color disabled in batch mode: see

     * Gets the one-based index of the line containing the error.
     *
     * @return The one-based index of the line containing the error or a non-positive value if unknown.
     */
    public int getLineNumber() {
        return lineNumber;
    }

    /**
     * Gets the one-based index of the column containing the error.
     *
     * @return The one-based index of the column containing the error or non-positive value if unknown.

     * Gets the one-based index of the line containing the error.
     *
     * @return The one-based index of the line containing the error or a non-positive value if unknown.
     */
    public int getLineNumber() {
        return lineNumber;
    }

    /**
     * Gets the one-based index of the column containing the error.
     *
     * @return The one-based index of the column containing the error or non-positive value if unknown.

     * Gets the one-based index of the line containing the error.
     *
     * @return The one-based index of the line containing the error or a non-positive value if unknown.
     */
    public int getLineNumber() {
        return lineNumber;
    }

    /**
     * Gets the one-based index of the column containing the error.
     *
     * @return The one-based index of the column containing the error or non-positive value if unknown.

     * @param message The detail message of the problem, may be {@code null}.
     * @param line The one-based index of the line containing the problem or {@code -1} if unknown.
     * @param column The one-based index of the column containing the problem or {@code -1} if unknown.
     * @param cause The cause of the problem, may be {@code null}.
     */

    return construct(e1);
  }

  /**
   * Returns an immutable list containing the given elements, in order.
   *
   * @throws NullPointerException if any element is null
   */
  public static <E> ImmutableList<E> of(E e1, E e2) {
    return construct(e1, e2);
  }

  /**
   * Returns an immutable list containing the given elements, in order.
   *
   * @throws NullPointerException if any element is null