index.jsp页面用来读取request中的list :即留言信息
SelectServlet用来把留言信息保存到list中
@WebServlet( "/SelectServlet")
public class SelectServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
MessageDAO messageDAO=new MessageDAO();
request.setCharacterEncoding("UTF-8");
String author=request.getParameter("author");
if(null == author || "" == author){
request.setAttribute("messageList",messageDAO.getAllMessage());
}else{
request.setAttribute("messageList",messageDAO.selectByAuthor(author));
}
request.getRequestDispatcher("index.jsp").forward(request,response); //页面转发
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}
}
index.jsp页面
<%
}
List messages= (List)request.getAttribute("messageList");
if(null != messages){
for(Message msg:messages){
%>
-
<%=msg.getAuthor()%> 发表于<%=msg.getDate()%>
<%
if(null!=user){
if( (1==tag) || ( author.equals(msg.getAuthor()) && 0==tag )){
%>
<%=msg.getContext()%>
<%
} //end of for(Message msg:messages){
}
%>
运行结果为:
当启动服务器后,第一次点击进入http://localhost:8080/MessageBoard/SelectServlet时:
当我刷新地址栏时:
就显示不出来了
也就是说只能访问一次?
请问如何解决