public Path getRequiredPath(List<String> keyAliases, Predicate<Path> constraint, String message) {
        return Optional
            .ofNullable(getPath(keyAliases, null, constraint, message))
            .orElseThrow(() -> InvalidOptionConfigurationException.requiredValue(keyAliases, "path"));
    }
As {@link #getPath(List, Path, Predicate, String)}, but additionally throw an exception if no value is
provided.

@throws InvalidOptionConfigurationException if a constraint violation occurs or if no value was provided.
@see #getString(List, String, Predicate, String)
common/config/src/main/java/io/apiman/common/config/options/GenericOptionsParser.java