See images of mysql in jsp

a query when I want to see some images that I upload to mysql on my page does not show me the image, I do not understand the error I hope you can help me.

Code to upload:

     String cadena1,usu,pass;
        int tamaño;

       Image i;
      String img;
       if(request.getParameter("btnaceptar")!= null){
          usu=request.getParameter("datos");
           pass=request.getParameter("carrera");
          img= request.getParameter("imagen");

          cadena1="INSERT INTO 'candidata' ('id_candidata', 'datos', 'carrera', 'imagen') VALUES (NULL, '"+usu+"', '"+pass+"', '"+img+"')";  
          accion(cadena1);
          sesion.setAttribute("usuario", usu);
            response.setHeader("Refresh", "1; URL=reguistrar_candidata.jsp");  
          }else{
       }
        %>





   <div class="container" >
        <table class="table" style="background-color: #ccc">
             <thead >
            <tr>
                <td><span class="label label-danger">ID</span></td>
                <td><span class="label label-danger">Datos</span></td>
                <td><span class="label label-danger">Carrera</span></td>
                <td><span class="label label-danger">Imagen</span></td>           
            </tr> 
             </thead>
              <tbody>
      <%  ResultSet rs;
        String cadena;
        //  Image i=null;
        //byte[] cad= new byte[6];
        cadena="select * from candidata";
        rs=Mostrar_datos(cadena);
        while(rs.next()){

      %>
codigo para votar:

      <%  ResultSet rs;
  int salto=0;
  String cadena;
        //  Image i=null;
        //byte[] cad= new byte[6];
        cadena="select datos,imagen,id_candidata from candidata";
        rs=Mostrar_datos(cadena);
        while(rs.next()){

      %>

                <th id="grad4"><a href="votar.jsp?codigo=<%=rs.getString(3)%>"><img src="Imagen/<%=rs.getString(2) %>" width="100" height="300"><br>
                        <span class="label label-danger"><%=rs.getString(1) %></span>  <br>
                             </a> </th>
                <%
                        salto++;
                        if(salto == 6){
                            %>



                            <%
                            salto = 0;
                        } 
                    }
          %>

         </tbody>  
           <%  
        String cadena1,cod;

          cod=request.getParameter("codigo");
       if(cod != null){ 
       cadena1="INSERT INTO 'votos' ('id_votos', 'id_candidata') VALUES (NULL, '"+cod +"')";  
         accion(cadena1);
          }else{
          }

        %>