Send parameters in ACLMessage

Question

I send a message from one agent to another

msg.setContent("price: 30, count: 1");

After that I need to manually parse it. Is there more convenient way to transfer parameters without converting to string? For example, send some container..

Answer 1

You had better use an ontology. It is more convenient way. For example.

Create your container:

public class ParameterConcept implements Predicate{
    private Long price;
    private Long count;
    ... getters and setters
}

Create your ontology:

public class YourOntology extends Ontology {
    public static final String NAME = "YourOntology";
    private static Ontology instance = new YourOntology();
    public static Ontology getInstance() {
        return instance;
    }

    private YourOntology() {
        super(NAME, BasicOntology.getInstance());

        add(new PredicateSchema("ParameterConcept"), ParameterConcept.class);
        PredicateSchema parameterConcept = (PredicateSchema) getSchema("ParameterConcept");
        parameterConcept.add("price",         (PrimitiveSchema) getSchema(BasicOntology.INTEGER), ObjectSchema.MANDATORY);
        parameterConcept.add("count",         (PrimitiveSchema) getSchema(BasicOntology.INTEGER), ObjectSchema.MANDATORY);
    }
}

Register your ontology like this (YourAgent.java):

private static final Codec codec = new SLCodec();
private static final Ontology ontology = YourOntology.getInstance();

protected void setup() {
    getContentManager().registerLanguage(codec, FIPANames.ContentLanguage.FIPA_SL0);
    getContentManager().registerOntology(ontology);
}

Create message like this:

ACLMessage msg = new ACLMessage(ACLMessage.INFORM);
...
msg.setLanguage(FIPANames.ContentLanguage.FIPA_SL0);
msg.setOntology(YourOntology.NAME);
...
try {
    agent.getContentManager().fillContent(msg, parameterConcept);
} catch (Exception e) {
     throw new RuntimeException("cannot fill message.", e);
}

Now you can parse message (code of the other agent) like this:

ContentManager cm = myAgent.getContentManager();
ContentElement contentElement = cm.extractContent(aclMessage);
ParameterConcept pc = (ParameterConcept) contentElement;

Or you can just use json with third json libs.

Answer 2

You could just use msg.setContentObject() method and pass object with class that implements Serializable interface.