Jadex bdiv3 goal parameters: there can only be one?

[sdr3]

Hello!

So i think i have discovered something, either a limitation of jadex or an extension of my ignorance. I tried creating multiple GoalParameters in a goal and then extracting those parameters in a triggered plan, jadex seems to only take the first GoalParameter and ignore the rest. I have tested this by modifying the tutorial D5 of the BDIv3 Tutorial set. The source code is placed below.

I extended the Translate goal to have two String parameters :

• eword --> the english word to translate
• lang --> the language that the english word should be translated into

The triggered plan (TranslateToGermanPlan) takes these parameters into its constructor and stores them locally as class fields. The PlanPrecondition then makes sure that the lang Goal Parameter is "german". The output of this agent when the Goal is triggered is as follows:

Using stored platform password: b5b6e1fb-e8d
LMxxxxx9_fc5 platform startup time: 2351 ms.
Commencing Agent Body
Creating Translate to german plan
eword value: bugger
lang value: bugger
Checking language

as you can see the eword and lang have both been set to "bugger" which is the eword value. My original assumption was that if the variable names were the same (ie. "eword" and "lang") in both goal and plan, jadex would map them accordingly. Have I done something wrong or is this a limitation of @GoalParameter annotation

==================== source code======================

@Agent
@Description("A Translation Agent A1.
Implments a top-level goal.")
public class TranslationBDI {

@AgentFeature
IBDIAgentFeature bdiFeature;

@AgentFeature
IExecutionFeature execFeature;

@Belief
Map<String, String> wordtable = new HashMap<String, String>();

@AgentCreated
public void init(){
    wordtable.put("coffee", "Kaffee");
    wordtable.put("milk", "Milch");
    wordtable.put("cow", "Kuh");
    wordtable.put("cat", "Katze");
    wordtable.put("dog", "Hund");

}

// Inner Class Goal
@Goal
public class Translate{

    @GoalParameter
    protected String eword;

    @GoalParameter
    protected String lang;

    @GoalResult
    protected String gword;

    public Translate(String eword, String lang){
        this.eword = eword;
        this.lang = lang;
    }

}

@Plan(trigger=@Trigger(goals=Translate.class))
public class TranslateToGermanPlan{

    protected String eword;
    protected String lang;

    @PlanPrecondition
    public boolean checklangGerman(){
        System.out.println("Checking language");
        return this.lang.equals("german");
    }

    public TranslateToGermanPlan(String eword, String lang){
        System.out.println("Creating Translate to german plan");
        System.out.println("eword value: " + eword);
        System.out.println("lang value: " + lang);
        this.eword = eword;
        this.lang = lang;
    }

    @PlanBody
    public void body(){
        String ret = wordtable.get(eword);
    }


}

@AgentBody
public void body(){

    System.out.println("Commencing Agent Body");

    execFeature.waitForDelay(3000, new IComponentStep<Void>(){

        @Override
        public IFuture<Void> execute(IInternalAccess ia) {
            System.out.println("Three seconds have past.");
            System.out.println("Adding word bugger to wordtable");
            wordtable.put("bugger", "Flegel");
            return IFuture.DONE;
        }

    });


    String eword = "bugger";
    String gword = (String)bdiFeature.dispatchTopLevelGoal(new Translate(eword, "german")).get();
    System.out.println("Translate: " + eword + " " + gword);


}

}

[Lars Braubach]

Hi Steve,

the problem is that using only a java constructor for injecting different kinds of values is difficult, because in Java the parameter names are not preserved in the class file. This means we do not have access to "eword" and "lang" during the injection phase. Hence we can only do type matching which is a best effort approach.

public TranslateToGermanPlan(String eword, String lang){

Our solution here is that you can just inject the pojo goal itself using the following code instead

public TranslateToGermanPlan(Translate goal){

From the goal you can access its parameters in the usual Java way.

Best
Lars

[sdr3]

Hi Lars,

Thank you for the reply. I see the problem, it makes sense. It doesnt seem a big problem to obtain values from teh goal itself :)

Kind regards