VocabularyInterface.php

<?php

namespace Drupal\taxonomy;

use Drupal\Core\Config\Entity\ConfigEntityInterface;

/**
 * Provides an interface defining a taxonomy vocabulary entity.
 */
interface VocabularyInterface extends ConfigEntityInterface {
    
    /**
     * Denotes that no term in the vocabulary has a parent.
     */
    const HIERARCHY_DISABLED = 0;
    
    /**
     * Denotes that one or more terms in the vocabulary has a single parent.
     */
    const HIERARCHY_SINGLE = 1;
    
    /**
     * Denotes that one or more terms in the vocabulary have multiple parents.
     */
    const HIERARCHY_MULTIPLE = 2;
    
    /**
     * Returns the vocabulary description.
     *
     * @return string
     *   The vocabulary description.
     */
    public function getDescription();

}