public InputSource(Collection<InputSource> inputs) {
        this.modelId = null;
        this.location = null;
        this.inputs = ImmutableCollections.copy(inputs);
    }

    /**
     * Get the path/URL of the POM or {@code null} if unknown.
     *
     * @return the location
     */
    public String getLocation() {
        return this.location;
    }

    /**