A Datagrid is one of the standard components of JavaServer Faces (
JSF), but it is not part of the Struts framework. In Struts, you have to create your own tables of data using standard HTML and Struts tags such as <logic:iterate>. Also, Struts does not have any special features for adding/updating/deleting data in a relational database. You must either adopt another framework such as Hibernate or the new
Java EE Persistence framework, or use the standard
JDBC API to do this.
You might look to other projects such as
The Display tag library for automated features to build grids or tables of data on your pages.