HashMap value값 Object 사용

HashMap<String, Object> everyone = new HashMap<String, Object>();

    everyone.put("사람" ,  new 사람());
    everyone.put("원숭이", new 원숭이());
    everyone.get("사람").말하다();
    everyone.get("원숭이").말하다();
    ((사람)everyone.get("사람")).말하다();

//오브젝트로 벨류타입 선언 후 다른타입 넣을때 형변환 시켜줘야함