ACTF's power stems from two key features.
First, its validation mechanism is model neutral and, second,
it supports a variety of scripting languages to aid in expressing sophisticated validation rules.
These features are embodied in two attributes of the root <actf:rulebase>
tag,
namely, the actf:model and actf:scriptlang attributes.
ACTF can support any number of "models" for validating and inspecting GUIs
and can also support a host of languages other than JavaScript for writing expressions,
including Java itself.