Friday, March 13, 2009

How does a servlet communicate with a JSP page (JSP)

Question :How does a servlet communicate with a JSP page? (JSP)
Answer :The following code snippet shows how a servlet instantiates a bean and
initializes it with FORM data posted by a browser. The bean is then placed
into the request, and the call is then forwarded to the JSP page, Bean1.jsp,
by means of a request dispatcher for downstream processing.
public void doPost (HttpServletRequest request, HttpServletResponse
response) {
try {
govi.FormBean f = new govi.FormBean();
String id = request.getParameter("id");
//use the id to compute
//additional bean properties like info
//maybe perform a db query, etc.
// . . .
("/jsp/Bean1.jsp").forward(request, response);
} catch (Exception ex) {
. . .
The JSP page Bean1.jsp can then process fBean, after first extracting it
from the default request scope via the useBean action.
jsp:useBean id="fBean" class="govi.FormBean" scope="request"/
jsp:getProperty name="fBean" property="name" / jsp:getProperty
name="fBean" property="addr" / jsp:getProperty name="fBean"
property="age" / jsp:getProperty name="fBean"
property="personalizationInfo" /

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