How will you pass values from HTML page to the Servlet

First we put the values to be passed inside a HTML form and then call the servlet in the form action. To catch the form fields values we simply call the getParameter method of the HttpServletRequest, supplying the parameter name as an argument. The return value is a String corresponding to the first occurrence of that parameter name. An empty String is returned if the parameter exists but has no value, and null is returned if there was no such parameter.

If the parameter could potentially have more than one value we should call getParameterValues instead of getParameter. This returns an array of strings. To get a full list of parameters we can use getParameterNames which returns an Enumeration, each entry of which can be cast to a String and used in a getParameter call.