Question

我有一个查询数据库并创建arraylists（也就是对象）的Servlet。

这个Servlet包含在一个JSP页面中，用于打印arraylists＆＃39;内容，但我不知道如何将它们从Servlet传递给JSP。

如何让JSP从Servlet中获取这些对象？

这是我的Servlet代码：

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    //CREATING CONTAINERS THAT WILL BE FORWARDED
    ArrayList<Volet> voletList = new ArrayList<Volet>();
    ArrayList<Critere> critereList = new ArrayList<Critere>();
    PrintWriter writer = response.getWriter(); 
    try {  
        //CONNEXION TO DATABASE:
        Class.forName("oracle.jdbc.OracleDriver");
        Connection con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:oracle", "OCP", "oracle11g");
        Statement st = con.createStatement();
        //SQL REQUEST
        String sqlVolet = "select * from ocp.volet";
        ResultSet rsVolet = st.executeQuery(sqlVolet);
        //WRITING FROM SQL RESULT INTO CONTAINER LIST:
        while(rsVolet.next())
        {
            Volet volet = new Volet();
            volet.setId(rsVolet.getInt(1));
            volet.setDescription(rsVolet.getString(2));
            voletList.add(volet);
        }

        String sqlCritere = "select * from ocp.critere";
        ResultSet rsCritere = st.executeQuery(sqlCritere);
        while(rsCritere.next())
        {
            Critere critere = new Critere();
            critere.setId(rsCritere.getInt(1));
            critere.setDescription(rsCritere.getString(2));
            critere.setVoletid(rsCritere.getInt(3));
            critereList.add(critere);
        }

        //CLOSING DATABASE CONNEXION:
        con.close();
        //DISPATCH THE CONTAINER THROUGH FORWARD

    }
    catch(Exception e)
    {
        RequestDispatcher requestDispatcher =   request.getRequestDispatcher("/View/ErrorPage.jsp");
        request.setAttribute( "e", e );
        requestDispatcher.forward(request, response);
    }
}

P.S。我试图将对象转发到JSP，但它没有用。

Answer 1

在servlet代码中使用request.setAttribute

request.setAttribute("attributeName",attributeValue);
RequestDispatcher reqDispatcher = getServletConfig().getServletContext().getRequestDispatcher("JSP file path");
reqDispatcher.forward(request,response);

并在jsp代码中使用request.getAttribute并键入caste it到实际对象类型。

ClassType attributeValue= (ClassType) request.getAttribute("attributeName");

如何从JSP中包含的Servlet获取对象？

1 个答案: