/**
  * Get singleton instance
  *
  * @access public
  * @return object Singleton instance
  */
 public static function getInstance()
 {
     // optionally create new instance
     if (!self::$instance) {
         self::$instance = new KocujSitemapPluginCache();
     }
     // exit
     return self::$instance;
 }
 /**
  * Get sitemap to display
  *
  * @access public
  * @param string $title Sitemap title - default: empty
  * @param string $class Sitemap class - default: empty
  * @return string Sitemap to display
  */
 public function getSitemap($title = '', $class = '')
 {
     // declare global
     global $classKocujSitemapAdmin;
     // get arguments
     if (empty($title)) {
         KocujSitemapPluginMultiLang::getInstance()->beforeGetBlogName();
         $title = apply_filters('kocujsitemap_defaulttitle', KocujSitemapPluginMultiLang::getInstance()->getTranslatedBlogName(), get_locale());
         KocujSitemapPluginMultiLang::getInstance()->afterGetBlogName();
     }
     if (empty($class)) {
         $class = apply_filters('kocujsitemap_defaultclass', '');
     }
     $title = apply_filters('kocujsitemap_linktitle', $title, 0, 'home', get_locale());
     // initialize
     $output = '';
     // load cache
     if (!KocujSitemapPluginCache::getInstance()->loadCache($title, $output, get_locale())) {
         KocujSitemapPluginCache::getInstance()->createCache();
         if (!KocujSitemapPluginCache::getInstance()->loadCache($title, $output, get_locale())) {
             return '';
         }
     }
     // optionally set footer
     $footer = '';
     $value = $classKocujSitemapAdmin->getConfigClass()->getOption('PoweredBy');
     if (!empty($value)) {
         $footer = '<div class="kocujsitemapfooter">' . sprintf(__('Powered by %s plugin', 'kocuj-sitemap'), '<a href="http://kocujsitemap.wpplugin.kocuj.pl/" rel="external">Kocuj Sitemap</a>') . '</div>';
     }
     // show begin and end
     if (!empty($output)) {
         $classText = '';
         if (!empty($class)) {
             $classText = ' ' . $class;
         }
         $html5 = $classKocujSitemapAdmin->getConfigClass()->getOption('UseHTML5');
         if (!empty($html5)) {
             $tagBegin = KocujSitemapPluginHTML5::getInstance()->getTagNavBegin('', 'kocujsitemap' . $classText);
             $tagEnd = KocujSitemapPluginHTML5::getInstance()->getTagNavEnd();
         } else {
             $tagBegin = '<div class="kocujsitemap' . $classText . '">';
             $tagEnd = '</div>';
         }
         $output = $tagBegin . $output . $footer . $tagEnd;
     }
     // exit
     return $output;
 }
 /**
  * Cron
  *
  * @access public
  * @return void
  */
 public function cron()
 {
     // create cache
     KocujSitemapPluginCache::getInstance()->createCache();
 }