If JasperAssistant plug-in does not appear to be accessible after the installation, then the plug-in may require to be enabled manually:
From the menu, select Product Configuration Dialog, first make sure that is toggled to ON in the toolbar.. In the
Now drill down in the Eclipse Platform tree view. Both the Graphical Editing Framework (GEF) and JasperAssistant need to be present (if not, they are not installed) and enabled.
Under Eclipse 3.0 it is possible that after this action the plug-in is still not
accessible. In this case, simply delete the
configuration folder under the Eclipse installation directory and restart
the IDE. Note that this is a safe operation that does not affect any important
configuration data. Alternatively, you can start Eclipse using the following command