Duplicate Entry add to database

Question

Good day! I'm having some problem when adding a array to my database.. i'm using JSP and MySql.. the problem is when I submit my form and another page add the list it duplicates. by if i refresh the page it doesn't duplicate..
String str_spc ="";
String str_ind ="";
int SQLstatus1=0;
int SQLstatus2=0;
SQLstatus= statement.executeUpdate("Delete from pro_industry where usr_code ='"+(String)session.getValue("usercode")+"'");
SQLstatus = 0;
SQLstatus= statement.executeUpdate("Delete from pro_specialization where usr_code ='"+(String)session.getValue("usercode")+"'");
SQLstatus = 0;
String[] pro_ind = request.getParameterValues("SecondList");
String[] pro_spc = request.getParameterValues("FourthList");
for(int i = 0; i < pro_ind.length; i++)
{SQLstatus= statement.executeUpdate("Insert into pro_industry (usr_code,ind_code) values ('"+(String)session.getValue("usercode")+"','"+pro_ind[i]+"')");
out.println((i+1)+"="+pro_ind[i]+"<br>");
SQLstatus = 0;
for(int i = 0; i < pro_spc.length; i++)
{SQLstatus1= statement.executeUpdate("Insert into pro_specialization (usr_code,spc_code) values ('"+(String)session.getValue("usercode")+"','"+pro_spc[i]+"')");
out.println((i+1)+"="+pro_spc[i]+"<br>");
SQLstatus1 = 0;
SQLstatus2=statement.executeUpdate("Update applicant set lvl_code ='"+request.getParameter("lvl_list")+"' where usr_code ="+(String)session.getValue("usercode"));
session.putValue("lvl_code",request.getParameter("lvl_list"));
%>

Answer 1

Hi All
I got the solution for this problem.
I found the following methods in Action.java which I think may help to control the session ID. That means if the user submits the page and press the back button or and submit the page or refresh the page again it will throw an error.
generateToken(HttpServletRequest request)
saveToken(HttpServletRequest request)
isTokenValid(HttpServletRequest request)
You can use like this
if (isTokenValid(request)) {
resetToken(request);
// Guarded code, must only be executed once for the current token.
Regards,
Sandeep Patel
Techunified, Unified Technologies
Saudi Arabia , Riyadh
[email protected]