cartaction.java

达内网上购物系统

package org.whatisjava.dang.action;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessage;
import org.apache.struts.action.ActionMessages;
import org.apache.struts.actions.MappingDispatchAction;
import org.whatisjava.dang.domain.User;
import org.whatisjava.dang.form.CartItemForm;
import org.whatisjava.dang.service.CartService;
import org.whatisjava.dang.util.Constants;
import org.whatisjava.dang.util.CookieUtils;

public class CartAction extends MappingDispatchAction {

	public ActionForward show(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		CartService cs = getCartService(request);
		if (cs.isEmpty()) {
			ActionMessages errors = new ActionMessages();
			errors.add("error.cart.empty",
					new ActionMessage("error.cart.empty"));
			saveErrors(request, errors);

		}
		saveToCookie(response, cs);
		return mapping.findForward("success");
	}

	public ActionForward add(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		CartService cs = getCartService(request);
		CartItemForm f = (CartItemForm) form;
		boolean b = cs.addItem(f.getProductId());
		response.getWriter().write(b ? '1' : '0');
		return null;
	}

	public ActionForward update(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		CartService cs = getCartService(request);
		CartItemForm f = (CartItemForm) form;
		cs.updateNum(f.getProductId(), f.getNum());
		return mapping.findForward("success");
	}

	public ActionForward drop(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		CartService cs = getCartService(request);
		CartItemForm f = (CartItemForm) form;
		cs.drop(f.getProductId());
		return mapping.findForward("success");
	}

	public ActionForward recovery(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		CartService cs = getCartService(request);
		CartItemForm f = (CartItemForm) form;
		cs.recovery(f.getProductId());
		return mapping.findForward("success");
	}

	private CartService getCartService(HttpServletRequest request)
			throws Exception {
		HttpSession session = request.getSession();
		User user = (User) session.getAttribute(Constants.SID_USER);
		CartService cs = (CartService) session.getAttribute(Constants.SID_CART);
		if (cs == null) {
			cs = new CartService(user);
			String cartStr = CookieUtils.findCookie(request,
					CookieUtils.CART_ID);
			if (cartStr != null) {
				cs.load(cartStr);
			}
		}
		session.setAttribute(Constants.SID_CART, cs);
		return cs;
	}

	private void saveToCookie(HttpServletResponse response, CartService cs)
			throws Exception {
		CookieUtils.addCookie(response, CookieUtils.CART_ID, cs.serialize());
	}
}