What are the different scope valiues for the ?
The different scope values for are 1. page
2. request
3.session
4.application
How do I prevent the output of my JSP or Servlet pages from being cached by the browser?
You will need to set the appropriate HTTP header attributes to prevent the dynamic content output by the JSP page from being cached by the browser. Just execute the following scriptlet at the beginning of your JSP pages to prevent them from being cached at the browser. You need both the statements to take care of some of the older browser versions. <%
response.setHeader("Cache-Control","no-store"); //HTTP 1.1
response.setHeader("Pragma\","no-cache"); //HTTP 1.0
response.setDateHeader ("Expires", 0); //prevents caching at the proxy server
%>
How can I prevent the word "null" from appearing in my HTML input text fields when I populate them with a resultset that has null values?
You could make a simple wrapper function, like
<%!
String blanknull(String s) {
return (s == null) ? \"\" : s;
}
%>
then use it inside your JSP form, like
" >
What is the difference b/w variable declared inside a declaration part and variable declared in scriplet part?
Variable declared inside declaration part is treated as a global variable.that means after convertion jsp file into servlet that variable will be in outside of service method or it will be declared as instance variable.And the scope is available to complete jsp and to complete in the converted servlet class.where as if u declare a variable inside a scriplet that variable will be declared inside a service method and the scope is with in the service method.
Is there a way to execute a JSP from the comandline or from my own application?
There is a little tool called JSPExecutor that allows you to do just that. The developers (Hendrik Schreiber & Peter Rossbach ) aim was not to write a full blown servlet engine, but to provide means to use JSP for generating source code or reports. Therefore most HTTP-specific features (headers, sessions, etc) are not implemented, i.e. no reponseline or header is generated. Nevertheless you can use it to precompile JSP for your website