Saving servlet html input parameters and reuse it for later time

Question

Dear all,
I am using one of charting api (netcharts pro) to develop a j2ee based charting application (jsp/servlet).
One of the requirement is to be able to capture the user input (set of selections) and save it as simple file or even save it in a database, and reuse it at later time.
At later time user do not need to make a selection from the scratch, and user can re-select/re-open his file (or database record) and generate charts.
in practical words :
user can input thru request.getParameter() or reading set of parameters from file
I will appreciate if someone can lead me to pointers/link/idea.

Answer 1

Reading file is exactly the same as you do for a normal app.
BufferedReader br = new BufferedReader(new FileReader(
                          new File("someFilePathName")));
while(br.readLine()!= null)
    //do your stuff here
  }just put the above code into your servlet plus the relevant try,catch block. Put the blow info into your app's web.xml if you want this servlet loads once Tomcat starts.
<servlet>
<servlet-name>servletName</servlet-name>
<servlet-class>servletDir</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
Hope it helps.