d7f2e992_rt_Programming_Model__AX_2012___Description
[Concept] Report definition language (RDL) contract [Class] SrsReportRdlDataContract [When to override] Override when you must do the following: Add custom validation to parameters. Call super before you validate. Add custom initialization to your parameters. Add your own UI builder for the parameters. Use the SrsReportNameAttribute attribute on the overridden class to specify which report uses this contract, and to bind the contract to the report. Use this attribute for reports that bind to a query or data method to tie the contract to the report. [Description] 
A framework contract used for query-based, data method–based, and OLAP-based reports, and for reports that contain static parameters created in a report. This contract provides a weakly typed representation of parameters. It contains methods that can be used to get or set values. It also contains a map of parameter names and the SRSReportParameter class.
Report Programming Model [AX 2012]