Putting parameters in the link.
Using back quotes you can embed Java code to extract the parameters and place them in the link. For example:

<a href="/foo.jhtml?`request.getParameter("bar")`">example</a>

To learn more, Using Back Quotes.

The typical JHTML file is structured like this.

<importbean bean="/atg/dynamo/service/jdbc/RelationalViewDroplet">

<nucleus type=import>
  /atg/dynamo/droplet/ForEach
  /atg/dynamo/droplet/Switch
</nucleus>

<java type="import">
  java.util.*
  java.net.*
</java>

<java>
  List ll = (List) request.resolveName("/betweengo/BigList");
</java>