For example the user may want the parameter startDate=First Day of month or
7 days before today, etc.
Avoid having to use complex Java to do date functions. Possibly include this in the point & click expression builder. Add library of built-in date functions, and other non-date functions (e.g. strings). e.g. today-7 days etc. Look at salesforce.com as an example. This is connected with a new feature likely being added to JasperServer in Quartz
IAN: Look at moving this up in priority.