JADE笔记之：消息模板简介

MessageTemplate class 利用MessageTemplate可以针对ACLMessage的每个属性设置模式，以达到过滤消息的目的。为了可以构建更复杂的匹配规则，多个模式也可以进行and，or，not运算。最有用的一些规则或方法包括：通信行为匹配，发送者匹配，会话ID匹配。

比如MatchPerformative( performative ) 是通信行为的匹配。

这里 performative 可能是:

ACLMessage.INFORM

ACLMessage.PROPOSE

ACLMessage.AGREE

还有发送者匹配MatchSender( AID )，会话匹配MatchConversationID( String )，通信协议匹配MatchProtocol( String ) ，本体匹配MatchOntology( String)。

       比如：MessageTemplate mt = MessageTemplate.and( 

                  MessageTemplate.MatchPerformative( ACLMessage.INFORM ),

                  MessageTemplate.MatchSender( new AID( "a1",                                                         AID.ISLOCALNAME))) ;

相当于建立了一个模板，表示消息规则为INFORM行为并且发送者为“a1”。

接收过程如下：ACLMessage msg = receive( mt );

                   if (msg != null) { ... handle message }

                      block();

 

示例：package jadePrime.acl;

import jade.core.Agent;

import jade.core.AID;

import jade.core.behaviours.*;

import jade.lang.acl.*;

 

public class Template extends Agent {

       MessageTemplate mt1 = MessageTemplate.and( 

                  MessageTemplate.MatchPerformative( ACLMessage.INFORM ),

                  MessageTemplate.MatchSender( new AID( "a1",AID.ISLOCALNAME))) ;

 

           protected void setup()

           {

           // Send messages to "a1" and "a2"

          

               ACLMessage msg = new ACLMessage(ACLMessage.INFORM);

               msg.setContent( "Ping" );

               for (int i = 1; i<=2; i++)

                   msg.addReceiver( new AID( "a" + i, AID.ISLOCALNAME) );

 

               send(msg);

              

           // Set-up Behaviour 1

          

          

               addBehaviour(new CyclicBehaviour(this)

               {

                    public void action( )

                    { 

                       System.out.print("Behaviour ONE: ");

                       ACLMessage msg= receive( mt1 );

                       if (msg!=null

                           System.out.println( "gets " +  msg.getPerformative() + " from "                   +  msg.getSender().getLocalName() + "=" +  msg.getContent() );

                       else

                           System.out.println( "gets NULL" );

                       block();

                    }

               });

           // Set-up Behaviour 2

              addBehaviour(new CyclicBehaviour(this)

               {  

                    public void action()

                    { 

                       System.out.print("Behaviour TWO: ");

                       ACLMessage msg= receive();

                       if (msg!=null)

                           System.out.println( "gets "

                            +  msg.getPerformative() + " from "

                            +  msg.getSender().getLocalName() + "="

                            +  msg.getContent() );

                       else

                           System.out.println( "gets NULL" );

                       block();

                    }

               });

           }

 

 

}

package jadePrime.acl;

import jade.core.Agent;

import jade.core.behaviours.*;

import jade.lang.acl.*;

 

public class Responder extends Agent {

       protected void setup()

    {

        addBehaviour(new CyclicBehaviour(this)

        {

             public void action()

             {

                ACLMessage msg = receive();

                if (msg!=null) {

                      

                    ACLMessage reply = msg.createReply();

                    reply.setPerformative( ACLMessage.INFORM );

                    reply.setContent(" Gossip....." );

                    send(reply);

 

                    reply.setPerformative( ACLMessage.PROPOSE );

                    reply.setContent(" Really sexy stuff... cheap! " );

                    send(reply);

                 }

                 block();

             }

        });

    }

}

输出结果：