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//---PACKAGE DECLARATION--- |
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|
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//---IMPORTS--- |
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import java.net.Socket; |
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import java.io.IOException; |
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import java.util.ArrayList; |
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|
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/** |
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* An implementation of an agent station |
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* |
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* @author $Author: tdb1 $ |
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* @version $Id: TemplateClass.java,v 1.11 2001/03/22 21:50:41 tdb1 Exp $ |
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*/ |
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class AgentStation extends Station { |
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|
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//---FINAL / FINAL STATIC ATTRIBUTES--- |
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|
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/** |
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* The current CVS revision of this class |
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*/ |
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public static final String REVISION = "$Revision: 1.11 $"; |
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|
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public static final int DIRECT_LISTEN_PORT = 32497; |
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|
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public static final int PEER_LISTEN_PORT = 32498; |
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|
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//---STATIC METHODS--- |
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|
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/** |
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* Returns a reference to the singleton agent station in use |
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* |
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* @throws RuntimeException if not yet initialised |
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*/ |
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public static AgentStation getInstance() throws RuntimeException { |
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if (_instance == null) { |
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throw new RuntimeException("Cannot obtain instance to uninitialised AgentStation!"); |
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} |
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return _instance; |
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} |
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|
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/** |
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* Constructs and returns the singleton AgentStation class |
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* |
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* @throws RuntimeException if already initialised |
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*/ |
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public static AgentStation initialise(String name, String descriptiveName, String initialPeerHostname, int initialPeerPort) { |
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if (_instance != null) { |
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throw new RuntimeException("Already initialised!"); |
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} |
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_instance = new AgentStation(name, descriptiveName, initialPeerHostname, initialPeerPort); |
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return _instance; |
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} |
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|
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//---CONSTRUCTORS--- |
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|
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/** |
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* Starts up the agent station. |
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* This is a private method to ensure singleton pattern. |
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*/ |
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private AgentStation(String name, String descriptiveName, String initialPeerHostname, int initialPeerPort) { |
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_name = name; |
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_descriptiveName = descriptiveName; |
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|
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DirectAgentHandlerFactory directAgentHandlerFactory = new DirectAgentHandlerFactory(); |
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PeerHandlerFactory peerHandlerFactory = new PeerHandlerFactory(); |
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|
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Listener directAgentListener = new Listener(DIRECT_LISTEN_PORT, directAgentHandlerFactory); |
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Listener peerListener = new Listener(PEER_LISTEN_PORT, peerHandlerFactory); |
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|
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directAgentListener.start(); |
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peerListener.start(); |
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|
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// TESTING ONLY - Have one peer connection |
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if (initialPeerHostname != null) { |
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try { |
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_logger.write(toString(), Logger.DEBUG, "Establishing peer connection with - " + initialPeerHostname + ":" + initialPeerPort); |
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Socket socket = new Socket(initialPeerHostname, initialPeerPort); |
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|
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PeerHandler peerHandler = new PeerHandler(socket); |
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addPeer(peerHandler); |
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} catch (IOException e) { |
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_logger.write(toString(), Logger.ERROR, "I/O ERROR - " + e); |
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} |
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} |
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_logger.write(toString(), Logger.SYSINIT, "created"); |
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} |
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|
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//---PUBLIC METHODS--- |
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|
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//*** STATION SERVICES TO AGENTS *** |
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|
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public ArrayList getAllAgents() { |
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return _agentList; |
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} |
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|
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public ArrayList getAllPeers() { |
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return _peerList; |
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} |
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|
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public String getName() { |
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return _name + " - " + _descriptiveName; |
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} |
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|
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public void sendAgent(Agent agent, PeerHandler peerHandler) { |
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// NOTE - no support for restarting agent on a failed send. |
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agent.shutdown(); |
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((PeerHandler) _peerList.get(_peerList.indexOf(peerHandler))).sendAgent(agent); |
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} |
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|
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//*** OTHER PUBLIC METHODS *** |
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|
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public void addAgent(Agent agent) { |
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_logger.write(toString(), Logger.DEBUG, "registered agent"); |
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_agentList.add(agent); |
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} |
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|
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public void removeAgent(Agent agent) { |
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_agentList.remove(_agentList.indexOf(agent)); |
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_logger.write(toString(), Logger.DEBUG, "deregistered agent"); |
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} |
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|
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public void addPeer(PeerHandler peerHandler) { |
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_logger.write(toString(), Logger.DEBUG, "registered peer"); |
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_peerList.add(peerHandler); |
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} |
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|
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public void removePeer(PeerHandler peerHandler) { |
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_peerList.remove(peerHandler); |
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_logger.write(toString(), Logger.DEBUG, "deregistered peer"); |
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} |
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|
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/** |
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* Overrides the {@link java.lang.Object#toString() Object.toString()} |
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* method to provide clean logging (every class should have this). |
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* |
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* This uses the uk.ac.ukc.iscream.util.FormatName class |
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* to format the toString() |
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* |
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* @return the name of this class and its CVS revision |
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*/ |
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public String toString() { |
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return FormatName.getName( |
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_name, |
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getClass().getName(), |
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REVISION); |
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} |
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|
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//---PRIVATE/PROTECTED METHODS--- |
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|
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//---ACCESSOR/MUTATOR METHODS--- |
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|
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//---ATTRIBUTES--- |
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|
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/** |
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* This is the friendly identifier of the |
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* component this class is running in. |
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* eg, a Filter may be called "filter1", |
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* If this class does not have an owning |
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* component, a name from the configuration |
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* can be placed here. This name could also |
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* be changed to null for utility classes. |
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*/ |
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private String _name; |
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|
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/** |
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* This holds a reference to the |
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* system logger that is being used. |
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*/ |
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private Logger _logger = Logger.getInstance(); |
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|
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private String _descriptiveName; |
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|
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private ArrayList _agentList = new ArrayList(); |
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|
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private ArrayList _peerList = new ArrayList(); |
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|
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//---STATIC ATTRIBUTES--- |
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|
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/** |
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* Holds the reference to the singleton instance of his class |
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*/ |
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private static AgentStation _instance; |
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|
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|
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} |