public function getErrors() {
		if ($this->forbiddenClasses) {
			return $this->forbiddenClasses;
		}
		
		if ($this->useCache) {
			// Cache duration: 30 minutes.
			$this->forbiddenClasses = $this->cacheService->get("forbidden.classes.".__DIR__."/".json_encode($this->selfEdit));
			if ($this->forbiddenClasses != null) {
				return $this->forbiddenClasses;
			}
		}
		
		$this->analyze();
		return $this->forbiddenClasses;
	}