Custom JSP taglib lets you fill interactive AcroForm elements (like text input fields etc.) in your PDF files.
Custom JSP tags let you open some PDF with AcroForms (your template), fill the fields and stream the final PDF file to user`s browser.
For example:
<%@ page contentType="application/pdf" %>
<%@ taglib uri="taglib.tld" prefix="af" %>
<af:AcroForm template="bill.pdf">
<af:setField name="user">Joe Doe</af:setField>
<af:setField name="amount">$10,000</af:setField>
</af:AcroForm>
