public void borrowBook(String title) {
	    this.title = title;
	    if (catalog.length == 0) {
	        System.out.println("We don't have this book");
	    }
	    for (int i = 0; i < catalog.length; i++) {
	        if (title.equals(catalog[i].titleofbook) && catalog[i].isBorrowed() == false) {
	            catalog[i].Borrow();
	            System.out.println("You successfully borrowed " + catalog[i].getTitle());
	            break;
	        } else if (title.equals(catalog[i].titleofbook) && catalog[i].isBorrowed() == true) {
	            System.out.println("Sorry, this book is already borrowed.");
	            break;
	        } else if (title.equals(catalog[i].titleofbook) == false) {
	            System.out.println("Sorry, this book is not in our catalog");
	            break;
	        }
	    }   
	}