@Override
	public void checkOut(String borrower, String date) {
		if(state == 0){
			this.borrower = borrower;
			this.checkOutDate = date;
			this.state = 1;  // ϸ ¸ 1 ٲ.
			System.out.println("*"+this.title+"() Ǿϴ.");
			System.out.println(":"+this.borrower);
			System.out.println(":"+this.checkOutDate);	
		}else{
			System.out.println(" Ұ մϴ.");
		}
	}