How do I clear the parameter after form post?

Question

Hi. I am learning my first JSP and was trying to do a form post. However, I found that after successfully submit to the database. If I press F5 (Refresh) from browser, the data will be re inserted into database. How could I clear the parameter (action) after data insert. My code structure is as follow.
Thank you.
<%@ page import="java.sql.*" %>
<%! Connection conn;
PreparedStatement stmtInsert;
public void jspInit() {
try{ ... }catch(SQLException e){}
catch(ClassNotFoundException e){}
public void jspDestroy() {...}
%>
<% if (request.getParameter("action") == null ) { %>
<H2>Data Entry:</H2>
<FORM METHOD="post" ACTION="<%= request.getRequestURI() %>">
<INPUT TYPE="submit" NAME="Submit" VALUE="Submit">
<INPUT TYPE="reset" NAME="Reset" VALUE="Reset">
     <INPUT TYPE="hidden" NAME="action" VALUE="insert">
</FORM>
<% } else if (request.getParameter("action").equals("insert")) { %>
<%
try{
synchronized(stmtInsert){
stmtInsert.executeUpdate();
out.print("<br> Room has been inserted successfully");
// once successful...how could I change the action to null?
} catch (SQLException e){
%>

Answer 1

http://forum.java.sun.com/thread.jsp?forum=45&thread=78925