AttributeCheck.jsp

To work this example save this file in the jsp directory of ayour jakarta-tomcat-4.0.1. Open up the web browser and try your URL localhost:8080/examples/jsp/CallAttributeCheck.jsp This sample shows how the first object associated with the attribute "query" is not stored, Although the last is. Using attributes is a powerful technique for sharing infromation, like logon data, between JSP pages.

This JSP demonstrates how a JSP extracts all attributes that are availible to it and CallAttributeCheck.jsp generates a web page that displays the result. Unlike request parameters, only one value can be associated with a given name, thus you need to loop over all possible values. Instead you can just print out the name and value for each attribute.



AttributeCheck.jsp

< %@page import="java.util.*"%>

< html>
< head>
< title >Attribute Check< /title>
< /head>

< body>
< h1>Attribute Names and Values< /h1>
< hr/>
< p>
< %
   string name;
   string value;

   for( Enmumeration names = request.getAttributesNames();
               names.hasMoreElements() ;) {
      name = (String)names.nextElement() ;
       value = (String)request.getAttribute(name) ;

% >

< /p>
< font size="4">< %= name % > < /font>: < %= value % >
< % } % >
< /body>
< /html>


In order to demonstrate the use of the request attributes, you need to first set them and then call the attribute-listing JSP page. Using CallAttributeCheck.jsp first sets several attributes and illustrating that only the most recent binding is retained in the case of the "query" where two are listed.