/**
  * Clear the cache.
  */
 protected function clearCache()
 {
     self::$cache = array();
 }
 /**
  * @inheritdoc
  */
 protected function initialize(InputInterface $input, OutputInterface $output)
 {
     $this->output = $output;
     $this->stdErr = $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output;
     self::$interactive = $input->isInteractive();
 }