public String buy(HttpServletRequest request, HttpServletResponse response, Page page){
		String[] oiids=request.getParameterValues("oiid");
		List<OrderItem> ois = new ArrayList<>();
		float total = 0;

		for (String strid : oiids) {
			int oiid = Integer.parseInt(strid);
			OrderItem oi= orderItemDAO.get(oiid);
			total +=oi.getProduct().getPromotePrice()*oi.getNumber();
			ois.add(oi);
		}
		
		request.getSession().setAttribute("ois", ois);
		request.setAttribute("total", total);
		return "buy.jsp";
	}	

package tmall.servlet;

import java.io.BufferedWriter;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

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

import org.springframework.web.util.HtmlUtils;

import tmall.bean.Category;
import tmall.bean.OrderItem;
import tmall.bean.Product;
import tmall.bean.ProductImage;
import tmall.bean.PropertyValue;
import tmall.bean.Review;
import tmall.bean.User;
import tmall.comparator.ProductAllComparator;
import tmall.comparator.ProductDateComparator;
import tmall.comparator.ProductPriceComparator;
import tmall.comparator.ProductReviewComparator;
import tmall.comparator.ProductSaleCountComparator;
import tmall.dao.CategoryDAO;
import tmall.dao.ProductDAO;
import tmall.dao.ProductImageDAO;
import tmall.util.Page;

public class ForeServlet extends BaseForeServlet {
	public String home(HttpServletRequest request, HttpServletResponse response, Page page) {
		List<Category> cs= new CategoryDAO().list();
		new ProductDAO().fill(cs);
		new ProductDAO().fillByRow(cs);
		request.setAttribute("cs", cs);
		return "home.jsp";
	}

	public String register(HttpServletRequest request, HttpServletResponse response, Page page) {
		String name = request.getParameter("name");
		String password = request.getParameter("password");
		name = HtmlUtils.htmlEscape(name);
		System.out.println(name);
		boolean exist = userDAO.isExist(name);
		
		if(exist){
			request.setAttribute("msg", "用户名已经被使用,不能使用");
			return "register.jsp";	
		}
		
		User user = new User();
		user.setName(name);
		user.setPassword(password);
		System.out.println(user.getName());
		System.out.println(user.getPassword());
		userDAO.add(user);
		
		return "@registerSuccess.jsp";	
	}	
	public String login(HttpServletRequest request, HttpServletResponse response, Page page) {
		String name = request.getParameter("name");
		name = HtmlUtils.htmlEscape(name);
		String password = request.getParameter("password");		
		
		User user = userDAO.get(name,password);
		 
		if(null==user){
			request.setAttribute("msg", "账号密码错误");
			return "login.jsp";	
		}
		request.getSession().setAttribute("user", user);
		return "@forehome";	
	}	
	
	public String product(HttpServletRequest request, HttpServletResponse response, Page page) {
		int pid = Integer.parseInt(request.getParameter("pid"));
		Product p = productDAO.get(pid);
		
		List<ProductImage> productSingleImages = productImageDAO.list(p, ProductImageDAO.type_single);
		List<ProductImage> productDetailImages = productImageDAO.list(p, ProductImageDAO.type_detail);
		p.setProductSingleImages(productSingleImages);
		p.setProductDetailImages(productDetailImages);
		
		List<PropertyValue> pvs = propertyValueDAO.list(p.getId());		
	
		List<Review> reviews = reviewDAO.list(p.getId());
		
		productDAO.setSaleAndReviewNumber(p);

		request.setAttribute("reviews", reviews);

		request.setAttribute("p", p);
		request.setAttribute("pvs", pvs);
		return "product.jsp";		
	}
	public String logout(HttpServletRequest request, HttpServletResponse response, Page page) {
		request.getSession().removeAttribute("user");
		return "@forehome";	
	}

	public String checkLogin(HttpServletRequest request, HttpServletResponse response, Page page) {
		User user =(User) request.getSession().getAttribute("user");
		if(null!=user)
			return "%success";
		return "%fail";
	}
	public String loginAjax(HttpServletRequest request, HttpServletResponse response, Page page) {
		String name = request.getParameter("name");
		String password = request.getParameter("password");		
		User user = userDAO.get(name,password);
		
		if(null==user){
			return "%fail";	
		}
		request.getSession().setAttribute("user", user);
		return "%success";	
	}
	public String category(HttpServletRequest request, HttpServletResponse response, Page page) {
		int cid = Integer.parseInt(request.getParameter("cid"));
		
		Category c = new CategoryDAO().get(cid);
		new ProductDAO().fill(c);
		new ProductDAO().setSaleAndReviewNumber(c.getProducts());		
		
		String sort = request.getParameter("sort");
		if(null!=sort){
		switch(sort){
			case "review":
				Collections.sort(c.getProducts(),new ProductReviewComparator());
				break;
			case "date" :
				Collections.sort(c.getProducts(),new ProductDateComparator());
				break;
				
			case "saleCount" :
				Collections.sort(c.getProducts(),new ProductSaleCountComparator());
				break;
				
			case "price":
				Collections.sort(c.getProducts(),new ProductPriceComparator());
				break;
				
			case "all":
				Collections.sort(c.getProducts(),new ProductAllComparator());
				break;
			}
		}
		
		request.setAttribute("c", c);
		return "category.jsp";		
	}
	
	public String search(HttpServletRequest request, HttpServletResponse response, Page page){
		String keyword = request.getParameter("keyword");
		List<Product> ps= new ProductDAO().search(keyword,0,20);
		productDAO.setSaleAndReviewNumber(ps);
		request.setAttribute("ps",ps);
		return "searchResult.jsp";
	}

	public String buyone(HttpServletRequest request, HttpServletResponse response, Page page) {
		int pid = Integer.parseInt(request.getParameter("pid"));
		int num = Integer.parseInt(request.getParameter("num"));
		Product p = productDAO.get(pid);
		int oiid = 0;
		
		User user =(User) request.getSession().getAttribute("user");
		boolean found = false;
		List<OrderItem> ois = orderItemDAO.listByUser(user.getId());
		for (OrderItem oi : ois) {
			if(oi.getProduct().getId()==p.getId()){
				oi.setNumber(oi.getNumber()+num);
				orderItemDAO.update(oi);
				found = true;
				oiid = oi.getId();
				break;
			}
		}		

		if(!found){
			OrderItem oi = new OrderItem();
			oi.setUser(user);
			oi.setNumber(num);
			oi.setProduct(p);
			orderItemDAO.add(oi);
			oiid = oi.getId();
		}
		return "@forebuy?oiid="+oiid;
	}

	public String addCart(HttpServletRequest request, HttpServletResponse response, Page page) {
		int pid = Integer.parseInt(request.getParameter("pid"));
		Product p = productDAO.get(pid);
		int num = Integer.parseInt(request.getParameter("num"));
		
		User user =(User) request.getSession().getAttribute("user");
		boolean found = false;

		List<OrderItem> ois = orderItemDAO.listByUser(user.getId());
		for (OrderItem oi : ois) {
			if(oi.getProduct().getId()==p.getId()){
				oi.setNumber(oi.getNumber()+num);
				orderItemDAO.update(oi);
				found = true;
				break;
			}
		}		
		
		if(!found){
			OrderItem oi = new OrderItem();
			oi.setUser(user);
			oi.setNumber(num);
			oi.setProduct(p);
			orderItemDAO.add(oi);
		}
		return "%success";
	}
	public String buy(HttpServletRequest request, HttpServletResponse response, Page page){
		String[] oiids=request.getParameterValues("oiid");
		List<OrderItem> ois = new ArrayList<>();
		float total = 0;

		for (String strid : oiids) {
			int oiid = Integer.parseInt(strid);
			OrderItem oi= orderItemDAO.get(oiid);
			total +=oi.getProduct().getPromotePrice()*oi.getNumber();
			ois.add(oi);
		}
		
		request.getSession().setAttribute("ois", ois);
		request.setAttribute("total", total);
		return "buy.jsp";
	}	
}

<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8" isELIgnored="false"%>

<%@include file="include/header.jsp"%>
<%@include file="include/top.jsp"%>
<%@include file="include/cart/buyPage.jsp"%>
<%@include file="include/footer.jsp"%>

<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8" isELIgnored="false"%>
<div class="buyPageDiv">
  <form action="forecreateOrder" method="post">
  
	<div class="buyFlow">
		<img class="pull-left" src="img/site/simpleLogo.png">
		<img class="pull-right" src="img/site/buyflow.png">
		<div style="clear:both"></div>
	</div>
	<div class="address">
		<div class="addressTip">输入收货地址</div>
		<div>
		
			<table class="addressTable">
				<tr>
					<td class="firstColumn">详细地址<span class="redStar">*</span></td>
					
					<td><textarea name="address" placeholder="建议您如实填写详细收货地址，例如接到名称，门牌好吗，楼层和房间号等信息"></textarea></td>
				</tr>
				<tr>
					<td>邮政编码</td>
					<td><input  name="post" placeholder="如果您不清楚邮递区号，请填写000000" type="text"></td>
				</tr>
				<tr>
					<td>收货人姓名<span class="redStar">*</span></td>
					<td><input  name="receiver"  placeholder="长度不超过25个字符" type="text"></td>
				</tr>
				<tr>
					<td>手机号码 <span class="redStar">*</span></td>
					<td><input name="mobile"  placeholder="请输入11位手机号码" type="text"></td>
				</tr>
			</table>
			
		</div>

	</div>
	<div class="productList">
		<div class="productListTip">确认订单信息</div>
		
		<table class="productListTable">
			<thead>
				<tr>
					<th colspan="2" class="productListTableFirstColumn">
						<img class="tmallbuy" src="img/site/tmallbuy.png">
						<a class="marketLink" href="#nowhere">店铺：天猫店铺</a>
						<a class="wangwanglink" href="#nowhere"> <span class="wangwangGif"></span> </a>
					</th>
					<th>单价</th>
					<th>数量</th>
					<th>小计</th>
					<th>配送方式</th>
				</tr>
				<tr class="rowborder">
					<td  colspan="2" ></td>
					<td></td>
					<td></td>
					<td></td>
					<td></td>
				</tr>
			</thead>
			<tbody class="productListTableTbody">
				<c:forEach items="${ois}" var="oi" varStatus="st" >
					<tr class="orderItemTR">
						<td class="orderItemFirstTD"><img class="orderItemImg" src="img/productSingle_middle/${oi.product.firstProductImage.id}.jpg"></td>
						<td class="orderItemProductInfo">
						<a  href="foreproduct?pid=${oi.product.id}" class="orderItemProductLink">
							${oi.product.name}
						</a>
						
							<img src="img/site/creditcard.png" title="支持信用卡支付">
							<img src="img/site/7day.png" title="消费者保障服务,承诺7天退货">
							<img src="img/site/promise.png" title="消费者保障服务,承诺如实描述">
						
						</td>
						<td>
						
						<span class="orderItemProductPrice">￥<fmt:formatNumber type="number" value="${oi.product.promotePrice}" minFractionDigits="2"/></span>
						</td>
						<td>
						<span class="orderItemProductNumber">${oi.number}</span>
						</td>
						<td><span class="orderItemUnitSum">
						￥<fmt:formatNumber type="number" value="${oi.number*oi.product.promotePrice}" minFractionDigits="2"/>
						</span></td>
						<c:if test="${st.count==1}">
						<td rowspan="5"  class="orderItemLastTD">
						<label class="orderItemDeliveryLabel">
							<input type="radio" value="" checked="checked">
							普通配送
						</label>
						
						<select class="orderItemDeliverySelect" class="form-control">
							<option>快递 免邮费</option>
						</select>

						</td>
						</c:if>
						
					</tr>
				</c:forEach>				
				
			</tbody>
			
		</table>
		<div class="orderItemSumDiv">
			<div class="pull-left">
				<span class="leaveMessageText">给卖家留言:</span>
				<span>
					<img class="leaveMessageImg" src="img/site/leaveMessage.png">
				</span>
				<span class="leaveMessageTextareaSpan">
					<textarea name="userMessage" class="leaveMessageTextarea"></textarea>
					<div>
						<span>还可以输入200个字符</span>
					</div>
				</span>
			</div>
			
			<span class="pull-right">店铺合计(含运费): ￥<fmt:formatNumber type="number" value="${total}" minFractionDigits="2"/></span>
		</div>
		
	</div>

	<div class="orderItemTotalSumDiv">
		<div class="pull-right"> 
			<span>实付款：</span>
			<span class="orderItemTotalSumSpan">￥<fmt:formatNumber type="number" value="${total}" minFractionDigits="2"/></span>
		</div>
	</div>
	
	<div class="submitOrderDiv">
			<button type="submit" class="submitOrderButton">提交订单</button>
	</div>
  </form>		
</div>