public function inCompanies(array $req_companies)
    {
        $companies = new ArrayCollection();

        foreach ($req_companies as $company) {
            if ($company = trim($company) === '') {
                continue;
            }
            if ($companies->contains($company)) {
                continue;
            }
            $companies->add($company);
        }

        if (!$companies->isEmpty()) {
            $this->companies = $companies;
        }

        return $this;
    }