问题描述

如何在servlet中取到DAO中的list从而打印在jsp页面上

   public ProductBean searchinfom(String username){
          Connection conn = null;
          PreparedStatement pstmt = null;
          ResultSet rst = null;
         // ProductBean  product = new ProductBean();
          List<ProductBean> productList=new ArrayList<ProductBean>();

          try{
            conn = dataSource.getConnection();
            pstmt = conn.prepareStatement("SELECT * FROM userproduct WHERE username like ?");
            pstmt.setString(1,"%"+username+"%");
            rst = pstmt.executeQuery();
            while(rst.next()){
                ProductBean product=new ProductBean();
                product.setUsername(rst.getString("username"));
                product.setProduct_id(rst.getString("product_id"));
                product.setFaddress(rst.getString("faddress"));
                product.setSaddress(rst.getString("saddress"));
                product.setWeight(rst.getDouble("weight"));
                product.setPrice(rst.getDouble("price"));
                productList.add(product);
                //return product;
            }//else{
              //return  null;
            //}

         }catch(SQLException se){

             System.out.println("SQLException:"+se.getMessage());
             return null;

         }finally{
             try{
                conn.close();
             }catch(SQLException se){
             }
         }
        return null;
       }

}

public class QueryInformServlet extends HttpServlet{
       public void doPost(HttpServletRequest request,HttpServletResponse response)
                 throws ServletException,IOException{
        String username = request.getParameter("username");
        ProductDao productdao = new ProductDao();
        ProductBean product = productdao.searchinfom(username);
        ArrayList<ProductBean> productList=null;
          productList =new ArrayList<ProductBean>();
        //if(!productList.isEmpty()){

          request.getSession().setAttribute("productList",productList);

          RequestDispatcher view = request.getRequestDispatcher("/displayinform.jsp");
          view.forward(request, response);
       //}else{
       // RequestDispatcher view = request.getRequestDispatcher("/error.jsp");
       //   view.forward(request, response);
      //  }
      }
    }

<%@ page contentType="text/html;charset=utf-8"%>
<%@ page import="java.util.* ,com.bean.ProductBean"%>

productList=(ArrayList)session.getAttribute("productList");
for(ProductBean product:productList)
{
%>

用户名	商品号	发货地	收货地	重量	价格

解决方案

 <%
for (ProductBean product:productList)
{
    response.Write(product.get用户名());
        ...
}
%>