网上购物系统设计和实现课程设计
四、程序关键代码及效果图
1、过滤器代码：［只要doFilter()方法］
（1）adminfilter.java:
HttpServletRequest requ=(HttpServletRequest)req;
res.setCharacterEncoding("gb18030");
requ.setCharacterEncoding("gb18030");
HttpSession session=requ.getSession();
if(session.getAttribute("admin")==null){
PrintWriter out=res.getWriter();
out.println("[removed]");
out.println("alert('您还没有登录！');");
out.println("[removed].href='../login_admin.jsp';");
out.println("[removed]");
}else{
chain.doFilter(req, res);
}
（2）userfilter.java:
HttpServletRequest requ=(HttpServletRequest)req;
res.setCharacterEncoding("gb18030");
requ.setCharacterEncoding("gb18030");
HttpSession session=requ.getSession();
if(session.getAttribute("uname")==null){
PrintWriter out=res.getWriter();
out.println("[removed]");
out.println("alert('您还没有登录！');");
out.println("[removed].href='../login.html';");
out.println("[removed]");
}else{
chain.doFilter(req, res);
}
(3)Encodingfilter.java:
HttpServletRequest request=(HttpServletRequest)req;
request.setCharacterEncoding("gb18030");
HttpServletResponse response=(HttpServletResponse)res;
response.setCharacterEncoding("gb18030");
chain.doFilter(req, res);
}
2、Servlet代码：［只要doPost()或doGet()方法］
（1）add.java:
response.setContentType("text/html");
request.setCharacterEncoding("gb18030");
HttpSession session=request.getSession();
CartBean cb=new CartBean();
Vector<CartProduct> cart
=(Vector<CartProduct>)session.getAttribute("cart");
String id=request.getParameter("id");
if(cart==null){
cart=new Vector<CartProduct>();
}
cart=cb.addCart(cart,id);
session.setAttribute("cart",cart);
response.sendRedirect("cart.jsp");
}
（2）addproduct.java:
PrintWriter out=response.getWriter();
Product p = new Product();
SmartUpload su = new SmartUpload();
su.initialize(this.getServletConfig(), request, response);
su.setMaxFileSize(1024 * 1024 * 10);
su.setAllowedFilesList("JPG,jpg,gif,GIF");
