RegexActivator can be used in JAICF project to handle users' requests that strictly match some regular expression.

Learn more about regular expressions here.

All you need to use regular expressions activator in your JAICF project is to add regex activators to the scenarios and then append RegexActivator to the BotEngine's array of activators.

state("state1") {
    activators {
        regex("/start")
    }

    action {
        ...
    }
}

Learn more about activators here.

val helloWorldBot = BotEngine(
    scenario = HelloWorldScenario,
    activators = arrayOf(
        ...,
        RegexActivator,
        ...
    )
)

Once a RegexActivator activates some state, a RegexActivatorContext instance becomes available through an activator.regex variable in the action block of this state.

state("state1") {
    activators {
        regex("[^\\d]*((?<number>\\d+).*)+")
    }

    action {
        val number = activator.regex?.group("number")
        reactions.say("Your number is $number")
    }
}

Regular expressions are of course not such flexible and smart as a machine learning driven approaches like NLU engines. But in some cases it can be used to handle a strictly defined users' queries like "/start" message that is sent from Telegram messenger each time the user clicks on "Start" button of the chatbot.