JAVA Getting a Request Parameter in a JSP Page

Getting a Request Parameter in a JSP Page
In a GET request, the request parameters are taken from the query
string (the data following the question mark on the URL). For example,
the URL http://hostname.com?p1=v1&p2=v2 contains two request
parameters - - p1 and p2. In a POST request, the request parameters
are taken from both query string and the posted data which is encoded
in the body of the request.

This example demonstrates how to include the value of a request
parameter in the generated output:

Hello <b><%= request.getParameter("name") %></b>!

If the page was accessed with the URL:

http://hostname.com/mywebapp/mypage.jsp?name=John+Smith

the resulting output would be:

Hello <b>John Smith</b>!

If name is not specified on the query string, the output would be:

Hello <b>null</b>!

This example uses the value of a query parameter in a scriptlet:

<%
if (request.getParameter("name") == null) {
out.println("Please enter your name.");
} else {
out.println("Hello <b>"+request.getParameter(i)+"</b>!");
}
%>