There exists already the possibility to let some custom java class perform arbitrary executions within the context of a flow-step.
However it is still required to let those prepare everything in temp-tables that can get read-out via the <output><database>.
This limitation requires that what in design are quite free-form result-pages are modeled into records in a database.
In contrast the <http> output mechanism allows for quite arbitrary external text to be pulled through xreporter.
Therefore the idea is to provide something like <ouput><java class=".."><!-- nested configuration --> </java></output> to allow for more flexible output generation while still reusing all benefits of the xreporter framework (common styling for information parts, shared access control to data and reports, ...)