Creating a Simple Filter
A lot of filter technology is needed to build WebLogger, so to get familiar with that, let's take a look at an example. WebLogger works with both the request object holding the data sent from the browser and the response object sending data back to the browser. So how do you work with, for example, the response object to send data back to the browser? Say that you want to filter access to a JSP page named simple.jsp and that you want a filter to add some text to the output of this JSP sent back to the browser. Here's what that JSP page looks like—as it stands, all this page does is to display the text “Using a filter” in an <H1> HTML header:
<HTML> <HEAD> <TITLE>Using a filter</TITLE> </HEAD> <BODY> <H1>Using a filter</H1> ...
Get Java™ After Hours: 10 Projects You'll Never Do at Work now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
