experimental/agents/BasicAgent.java

//---PACKAGE DECLARATION---

//---IMPORTS---
import java.io.ObjectOutputStream;
import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Iterator;
import java.util.ArrayList;
import java.util.Random;

/**
 * A basic implementation of the Agent abstract class
 *
 * @author  $Author: tdb1 $
 * @version $Id: TemplateClass.java,v 1.11 2001/03/22 21:50:41 tdb1 Exp $
 */
class BasicAgent extends Agent {

//---FINAL / FINAL STATIC ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public static final String REVISION = "$Revision: 1.11 $";
    
//---STATIC METHODS---

    /**
     * A bootstrap mechanism for an agent.
     * Essentially used to fire an agent direct into an agent station.
     *
     * @param args command line arguements
     *
     * @throws UnknownHostException if it can't find the agent station
     * @throws IOException if there is a problem firing the agent
     */
    public static void main(String[] args) throws IOException, UnknownHostException {
        System.out.println("Agent Bootstrapping Started.");
        if (args.length != 3) {
            throw new RuntimeException("Must specify an agent name and agent station hostname and port number on the command line!");
        }
        Agent instance = new BasicAgent(args[0]);
        Socket s = new Socket(args[1], Integer.parseInt(args[2]));
        ObjectOutputStream p = new ObjectOutputStream(s.getOutputStream());
        p.writeObject(instance);
        p.flush();
        s.close();
        System.out.println("Agent " + args[0] + " injected into " + args[1] + ":" + args[2]);
    }

//---CONSTRUCTORS---
    
    public BasicAgent(String name) {
        _name = name;
    }

//---PUBLIC METHODS---
    
    // *** AGENT LIFETIME ***
    
    public void run() {
        while(_running) {
            try {
                Thread.sleep(10000);
            } catch (InterruptedException e) {
            }
            ArrayList agents = _station.getAllAgents();
            Iterator i = agents.iterator();
            while(i.hasNext()) {
                Agent agent = (Agent) i.next();
                if (agent != (Agent) this) {
                    say("Saying hi to " + agent.getName());
                    agent.greet(this);
                }
            }
            say("Requesting to move on...");
            ArrayList peers = _station.getAllPeers();
            if (peers.size() > 1) {
                PeerHandler dstPeer = (PeerHandler) peers.get(new Random().nextInt(peers.size() - 1));
                _station.sendAgent(this, dstPeer);
            } else if (peers.size() == 1) {
                PeerHandler dstPeer = (PeerHandler) peers.get(0);
                _station.sendAgent(this, dstPeer);
            }
            say("No peers to move to...staying here.");
        }
    }
    
    //*** AGENT SERVICES ***    
    
    public void onArrival(Station station) {
        _transmissionCount++;
        _station = station;
        say("Just arrived at - " + _station.getName());
    }

    public void greet(Agent agent) {
        say(agent.getName() + " just said hi to me");
    }

    private void say(String text) {
        System.out.println("*** [" + getName() + "] " + text);
    }
    
    public String getName() {
        return _name;
    }
    
    public long getTransmissionCount() {
        return _transmissionCount;
    }

    /**
     * Used to shutdown this thread
     */
    public void shutdown() {
        _station = null;
        _running = false;
    }
    
    //*** OTHER PUBLIC METHODS ***

//---PRIVATE/PROTECTED METHODS---

//---ACCESSOR/MUTATOR METHODS---

//---ATTRIBUTES---

    /**
     * The name of the agent
     */
    private String _name;

    /**
     * A reference to the current AgentStation this agent is at
     */    
    private Station _station;
    
    /**
     * A "running" used by the main loop in the run() method to determine if
     * it should continue running this thread.
     */
    private boolean _running = true;
    
    /**
     * The number of times this agent has been transmitted between stations
     */
    private long _transmissionCount = 0;

//---STATIC ATTRIBUTES---

}
Revision:	1.2
Committed:	Fri May 4 02:04:35 2001 UTC (23 years ago) by ajm
Branch:	MAIN
Changes since 1.1:	+104 -21 lines
Log Message:	Loads of new framework but far from complete. The BasicAgent class is as it says, a basic agent, with ability to be run from the command line to fire it into an agentstation. AgentStations now have support for adding and removing agents and support for multiple listeners. Also initial support for peer agent stations. Attempted support at peer -> peer agent transfer, but run into problems. Still no bytecode transfer, but location and method has been figured out. The AgentSystem class is now the bootstrap class for an agent station. It brings up the AgentStation (which is now singleton) and the Logger (also singleton - using standard i-scream logging techniques). It is possible to specify a peer station that the booting agent station should connect to. Initial TODO: agent class loader agent bytecode transfer solve peer -> peer problems - possibly by creating extra socket to send agent, but shouldn't really be needed
#	User	Rev	Content
1	ajm	1.2	//---PACKAGE DECLARATION---
2	ajm	1.1
3	ajm	1.2	//---IMPORTS---
4			import java.io.ObjectOutputStream;
5			import java.io.IOException;
6			import java.net.Socket;
7			import java.net.UnknownHostException;
8			import java.util.Iterator;
9			import java.util.ArrayList;
10			import java.util.Random;
11
12			/**
13			* A basic implementation of the Agent abstract class
14			*
15			* @author $Author: tdb1 $
16			* @version $Id: TemplateClass.java,v 1.11 2001/03/22 21:50:41 tdb1 Exp $
17			*/
18			class BasicAgent extends Agent {
19
20			//---FINAL / FINAL STATIC ATTRIBUTES---
21
22			/**
23			* The current CVS revision of this class
24			*/
25			public static final String REVISION = "$Revision: 1.11 $";
26
27			//---STATIC METHODS---
28
29			/**
30			* A bootstrap mechanism for an agent.
31			* Essentially used to fire an agent direct into an agent station.
32			*
33			* @param args command line arguements
34			*
35			* @throws UnknownHostException if it can't find the agent station
36			* @throws IOException if there is a problem firing the agent
37			*/
38	ajm	1.1	public static void main(String[] args) throws IOException, UnknownHostException {
39	ajm	1.2	System.out.println("Agent Bootstrapping Started.");
40	ajm	1.1	if (args.length != 3) {
41			throw new RuntimeException("Must specify an agent name and agent station hostname and port number on the command line!");
42			}
43			Agent instance = new BasicAgent(args[0]);
44			Socket s = new Socket(args[1], Integer.parseInt(args[2]));
45			ObjectOutputStream p = new ObjectOutputStream(s.getOutputStream());
46	ajm	1.2	p.writeObject(instance);
47			p.flush();
48			s.close();
49			System.out.println("Agent " + args[0] + " injected into " + args[1] + ":" + args[2]);
50	ajm	1.1	}
51	ajm	1.2
52			//---CONSTRUCTORS---
53	ajm	1.1
54			public BasicAgent(String name) {
55			_name = name;
56			}
57	ajm	1.2
58			//---PUBLIC METHODS---
59
60			// * AGENT LIFETIME *
61	ajm	1.1
62			public void run() {
63			while(_running) {
64			try {
65			Thread.sleep(10000);
66			} catch (InterruptedException e) {
67			}
68			ArrayList agents = _station.getAllAgents();
69			Iterator i = agents.iterator();
70			while(i.hasNext()) {
71			Agent agent = (Agent) i.next();
72			if (agent != (Agent) this) {
73			say("Saying hi to " + agent.getName());
74			agent.greet(this);
75			}
76			}
77	ajm	1.2	say("Requesting to move on...");
78			ArrayList peers = _station.getAllPeers();
79			if (peers.size() > 1) {
80			PeerHandler dstPeer = (PeerHandler) peers.get(new Random().nextInt(peers.size() - 1));
81			_station.sendAgent(this, dstPeer);
82			} else if (peers.size() == 1) {
83			PeerHandler dstPeer = (PeerHandler) peers.get(0);
84			_station.sendAgent(this, dstPeer);
85			}
86			say("No peers to move to...staying here.");
87	ajm	1.1	}
88			}
89	ajm	1.2
90			//* AGENT SERVICES *
91
92			public void onArrival(Station station) {
93			_transmissionCount++;
94			_station = station;
95			say("Just arrived at - " + _station.getName());
96			}
97	ajm	1.1
98			public void greet(Agent agent) {
99			say(agent.getName() + " just said hi to me");
100			}
101
102			private void say(String text) {
103	ajm	1.2	System.out.println("*** [" + getName() + "] " + text);
104	ajm	1.1	}
105
106			public String getName() {
107			return _name;
108			}
109
110			public long getTransmissionCount() {
111			return _transmissionCount;
112			}
113	ajm	1.2
114			/**
115			* Used to shutdown this thread
116			*/
117			public void shutdown() {
118			_station = null;
119			_running = false;
120			}
121	ajm	1.1
122	ajm	1.2	//* OTHER PUBLIC METHODS *
123
124			//---PRIVATE/PROTECTED METHODS---
125
126			//---ACCESSOR/MUTATOR METHODS---
127
128			//---ATTRIBUTES---
129
130			/**
131			* The name of the agent
132			*/
133			private String _name;
134
135			/**
136			* A reference to the current AgentStation this agent is at
137			*/
138	ajm	1.1	private Station _station;
139	ajm	1.2
140			/**
141			* A "running" used by the main loop in the run() method to determine if
142			* it should continue running this thread.
143			*/
144			private boolean _running = true;
145
146			/**
147			* The number of times this agent has been transmitted between stations
148			*/
149	ajm	1.1	private long _transmissionCount = 0;
150	ajm	1.2
151			//---STATIC ATTRIBUTES---
152
153			}