The getServletContext() Method
The getServletContext() Method
(BookDBAO)getServletContext().
getAttribute(
"bookDBAO");
HttpSession session = request.getSession();
String selectedScreen = request.getServletPath();
ShoppingCart cart = (ShoppingCart)session.
getAttribute(
"cart");
if (cart == null) {
cart = new ShoppingCart();
session.setAttribute(
"cart", cart);
}
if (selectedScreen.equals(
"/bookcatalog")) {
bookId = request.getParameter(
"Add");
if (!bookId.equals(
"")) {
try {
book = bookDBAO.getBook(bookId);
if ( book.getOnSale() ) {
double sale = book.getPrice() * .85;
Float salePrice = new Float(sale);
book.setPrice(salePrice.floatValue());
}
cart.add(bookId, book);
} catch (BookNotFoundException ex) {
// not possible
}
}
} else if (selectedScreen.equals(
"/bookshowcart")) {
bookId =request.getParameter(
"Remove");
if (bookId != null) {
cart.remove(bookId);
}
clear = request.getParameter(
"Clear");
if (clear != null && clear.equals(
"clear")) {
cart.clear();
}
} else if (selectedScreen.equals(
"/bookreceipt")) {
// Update the inventory
try {
utx.begin();
bookDBAO.buyBooks(cart);
utx.commit();
} catch (Exception ex) {
try {
utx.rollback();
request.getRequestDispatcher(
"/bookordererror.jsp").
forward(request, response);
} catch(Exception e) {
System.out.println(
Programming Simple Tag Handlers
Chapter 8 · Custom Tags in JSP Pages
269
