6.11. Groups

A report can define a number of groups. Groups represent named expressions that determine the visual grouping of the related report data. Once declared, groups can be referred to throughout the report. JasperAssistant collects group definitions under a single Groups node in the Outline View. New groups can be added by using the context menu associated to this node.

A data group is identified using a group expression. Two consecutive data source lines are considered to be in the same group, if the group expression evaluates to the same value for both lines.


The grouping mechanism does not perform any sorting on the data supplied by the data source. The data provided by the data source must be already sorted so that the desired groups can be formed.

By declaring a group, two additional report sections can be added to the report: Group Header and Group Footer(Section 6.10, “Report Sections”).

Group Properties