易买网项目完工，把一些新知识记录下来，以便以后查阅，也方便他人借阅。介绍使用cookies查询商品详情。
第一步：建立商品实体类。
第二步：连接Oracle数据库。
第三步：使用三层架构。
效果图如下：
当我看中新疆牛肉干，商品点击时，进入查看商品详情页。
商品详情页：
核心代码如下：
<%
//创建商品业务逻辑对象
productBiz prodctbiz = new productBizImpl(); List<easybuy_product> productlist = prodctbiz.findproductList();
request.setAttribute("productlist",product);
%>
//EL表达式
核心架包
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
//EL表达式：
<c:forEach var="news" items="${requestScope.productlist}" > <li class="ck">
<dl>
<dt><a href="addcookie?id=${news.ep_id}"><img src="${news.ep_file_name}" /></a></dt>
<dd class="title"><a href="addcookie?id=${news.ep_id}">${news.ep_name}</a></dd>
<dd class="price">￥${news.ep_price}.00</dd>
</dl> </li> </c:forEach>
第二步：在Servlet创建addcookie.java页面,获取商品id：（注意：必须在web.xml写入）
<!--商品id存在cookies-->
<servlet>
<servlet-name>addcookie</servlet-name>
<servlet-class>Servlet.addcookie</servlet-class>
</servlet> <!-- 映射servlet -->
<servlet-mapping>
<servlet-name>addcookie</servlet-name>
<url-pattern>/addcookie</url-pattern>
</servlet-mapping>
package Servlet; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class addcookie extends HttpServlet { /**
* Constructor of the object.
*/
public addcookie() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { doPost(request, response);
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter();
request.setCharacterEncoding("utf-8");
//获取商品id
String id = request.getParameter("id");
//转发的页面
response.setHeader("refresh", "0;url=/yimaiWang/product-view.jsp?id="+id); Cookie[] cookies = request.getCookies(); String visitlist = null;
if (cookies != null) {
for (Cookie cookie : cookies) {
if (cookie.getName().equals("visitlist")) {
visitlist = cookie.getValue();
break;
}
}
if (visitlist == null) { Cookie cookie = new Cookie("visitlist", id);
cookie.setMaxAge(180);
response.addCookie(cookie); } else { String[] existIds = visitlist.split(",");
for (String exsitId : existIds) {
if (exsitId.equals(id)) { return;
}
} Cookie cookie = new Cookie("visitlist", visitlist + "," + id);
cookie.setMaxAge(180);
response.addCookie(cookie); }
} else { Cookie cookie = new Cookie("visitlist", id);
cookie.setMaxAge(180);
response.addCookie(cookie); }
} }
第三步：跳转商品详情页product-view.jsp(这俩个查询语句不同，一个是查询商品id，一个是商品List集合)
public easybuy_product findProductForid(int id) {
con=this.getConnection();
int i =id;
String sql = "select * from easybuy_product where ep_id =?";
easybuy_product pd = new easybuy_product();
try
{
st=con.prepareStatement(sql);
st.setInt(1,id);
rs=st.executeQuery();
while(rs.next())
{
pd.setEp_id(rs.getInt(1));
pd.setEp_name(rs.getString(2));
pd.setEp_description(rs.getString(3));
pd.setEp_price(rs.getInt(4));
pd.setEp_stock(rs.getInt(5));
pd.setEpc_id(rs.getInt(6));
pd.setEpc_child_id(rs.getInt(7));
pd.setEp_file_name(rs.getString(8));
}
} catch (SQLException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
return null;
}finally{
this.ShiFang(rs, st, con);
}
return pd;
}
}public List<easybuy_product> product(String id) {
List<easybuy_product> listproduct=new ArrayList<easybuy_product>();
// TODO Auto-generated method stub
con = this.getConnection();
String sql="select * from easybuy_product where ep_id=?";
try {
st=con.prepareStatement(sql);
st.setString(1,id);
rs=st.executeQuery();
while(rs.next()){
easybuy_product product = new easybuy_product();
product.setEp_id(rs.getInt(1));
product.setEp_name(rs.getString(2));
product.setEp_description(rs.getString(3));
product.setEp_price(rs.getInt(4));
product.setEp_stock(rs.getInt(5));
product.setEpc_id(rs.getInt(6));
product.setEpc_child_id(rs.getInt(7));
product.setEp_file_name(rs.getString(8));
listproduct.add(product);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
this.ShiFang(rs, st, con);
}
return listproduct;
}<%
//获取商品id
int id = Integer.parseInt(request.getParameter("id"));
productBiz bizvoid = new productBizImpl();
easybuy_product shop = bizvoid.findProductForid(id);
request.setAttribute("shop",shop);
%>
<%
//获取商品id
request.setCharacterEncoding("utf-8");
String a = request.getParameter("id");
%>
<% //创建商品信息业务逻辑对象
productBiz productbiz = new productBizImpl(); List<easybuy_product> list =productbiz.product(a);
request.setAttribute("list",list); %>
<div id="product" class="main">
<c:forEach var="product" items="${requestScope.list}" >
<h1><%=shop.getEp_name() %></h1>
</c:forEach>
<div class="infos">
<c:forEach var="product" items="${requestScope.list}" >
<div class="thumb"><img src="${product.ep_file_name}" width="300px" /></div>
<div class="buy">
<p>商品描述：<span class="price">${product.ep_description}</span></p>
<p>商城价：<span class="price">￥${product.ep_price}.00</span></p>
<c:if test="${product.ep_stock==null}">
<p class="w1 c">缺货</p>
</c:if>
<c:if test="${product.ep_stock!=null}">
<p class="w1 c">有货</p>
</c:if>
<c:if test="${name==null}">
<script type="text/javascript">
function ck(){
alert("你未登入，请去登入吧！");
return false;
}
</script> </c:if>