Comments on: How can I randomly display blocks of text in a .jsp file?

Question: How can I randomly display blocks of text in a .jsp file?

Kickstart70 — Sun, 25 Feb 2007 13:44:56 -0800

How do I output random blocks of text in a JSP include? I am not in any way a java/jsp programmer.

I have an application that uses JSP includes to display advertising (Google AdSense) to visitors. Currently, the ads are fairly static in size and content...I'd like to mix it up a little, have different sizes displayed, and occasionally have no ads at all.

Is there a way to do this just inside the .jsp file? Ideally I'd like to be able to specify what percentage of displays each will get (roughly...doesn't need to be perfect), like one ad block showing up 10% of the time and another 90%. That's not a requirement for this though.

Thanks!

By: delmoi

delmoi — Sun, 25 Feb 2007 14:02:08 -0800

You can do something like this:

<%
double d = Math.random();

if(d < 0.2){%>text block one<%}
else if(d < 0.4){%>text block 2%<%}
else {%>text block three<%}%>

By: delmoi

delmoi — Sun, 25 Feb 2007 14:02:19 -0800

Yes, that posted correctly!

By: delmoi

delmoi — Sun, 25 Feb 2007 14:06:49 -0800

(Oh wait, there is an extra "%" on the second line.)

Anyway, the numbers 0.2 and 0.4 control how often each block of text will be printed. The first block will be printed 20% of the time, the second block also 20% of the time (it will only print if d > .2 and d < 0.2) and the last block will print 60% of the time.br>
Also, that's just off the top of my head, so I don't know if the syntax is perfect.

By: comwiz

comwiz — Sun, 25 Feb 2007 15:04:16 -0800

Here's one that will work regardless of the number of text blocks you have:

< %br> ArrayList l = new ArrayList();
l.add("First string");
l.add("Second string");
l.add("Add as many of these as you want");

Response.getWriter().print(l.get(Math.random()*l.size()));

By: Civil_Disobedient

Civil_Disobedient — Sun, 25 Feb 2007 15:44:33 -0800

Can't you just do something like:

<%= "This is some text." %>

By: Civil_Disobedient

Civil_Disobedient — Sun, 25 Feb 2007 15:45:25 -0800

Sorry, missed the "random" part of the question.

By: AmbroseChapel

AmbroseChapel — Sun, 25 Feb 2007 16:09:12 -0800

You're attempting to change how Google AdSense ads display on your page? I'd say that was against their terms of service and therefore a Bad Idea.

By: Kickstart70

Kickstart70 — Sun, 25 Feb 2007 19:58:55 -0800

I'm not trying to change the way they display on the page...I just want different size ads to display, and occasionally some self-advertising, which isn't against the rules. Ie. sometimes I want a 336x280 ad, and sometimes I want a 300x250 ad.