kqml_travel_broker.java

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/* kqml_travel_broker.java
 * $Id: kqml_travel_broker.java,v 2.3 1997-11-19 19:22:41+09 ht Exp $ $Name: alpha5_1-release $
 */

package com.ibm.acl.kqml.interpreter;

import com.ibm.acl.kqml.*;
import com.ibm.acl.facilitator.FacilitatorProperties;
import com.ibm.acl.kqmlsample.travel.FlightInfo;

import java.io.IOException;
import java.util.*;

/**
 * Class kqml_travel_broker interprets the contents which written in 
 * language anAcl and ontology travel_broker. This class supports the following
 * performatives: broker-all, recruit-one, sorry, and error. 
 *
 * @version     $Revision: 2.3 $ $Date: 1997-11-19 19:22:41+09 $
 * @author      Hajime Tsuchitani
 */
public class kqml_travel_broker extends kqml_kqml_ontology {
  private static final String rcsid = "$Id: kqml_travel_broker.java,v 2.3 1997-11-19 19:22:41+09 ht Exp $ $Name: alpha5_1-release $";

  private boolean debug = KQMLManager.debug;
  /**
   * variable description goes here
   */
  private KQMLManager km;
  private  Conversation conv;
  /**
   * variable description goes here
   */
  private IDGenerator idgen;

  private String facilitator;  // url of the faclitator
  /**
   * Constructs kqml_travel_broker with no specified parameter.
   *
   */
  public kqml_travel_broker() {
    FacilitatorProperties fp;

    try {
      fp = new FacilitatorProperties();
    } catch (IOException ex) {
      ex.printStackTrace();
      return;
    }

    facilitator = fp.getOneURL("ktp");

    if (facilitator == null) {
      System.err.println(" no ktp facilitator found, system exit!");
      System.exit(1);
    }

    if (debug) 
      System.err.println(new Date() + 
        " > kqml_travel_broker.kqml_travel_broker(): faclitator url: " +
	facilitator);
  }

  /**
   * Conversation calls this method to interprete 
   * the content of the received KQML message.
   *
   * @param conversation reference to the Conversation
   * @param msg KQML message
   * @return true if message is interpreted successfully, otherwise false.
   * 
   */
  public synchronized boolean doInterpret(Conversation conversation,
					  KQML msg) {
    if (debug)
      System.err.println(new Date() + 
			 " > kqml_travel_broker.doInterpret(): entered");

    conv = (Conversation) conversation;

    km = conv.getKQMLManager();
    String performative = msg.getPerformative();

    if (performative.equalsIgnoreCase("broker-all")) {
      return doBrokerAll(conversation, msg);
    } else if (performative.equalsIgnoreCase("recruit-one")) {
      return doRecruitOne(conversation, msg);
    } else if (performative.equalsIgnoreCase("sorry")) {
      return doSorry(conversation, msg);
    } else if (performative.equalsIgnoreCase("error")) {
      return doError(conversation, msg);
    } else {
      return super.doInterpret(conv, msg);
    }
       
  }

  /**
   * Handles broker-all performative.
   * 
   * @param conversation reference to the Conversation
   * @param msg KQML message
   * @return true if message is interpreted successfully, otherwise false.
   * 
   */
  protected boolean doBrokerAll(Conversation conversation, KQML msg) {
    if (debug) 
      System.err.println(new Date() + 
        " > kqml_travel_broker.doBrokerAll entered");

    KQML rtnMsg = new KQML();

    Conversation conv = (Conversation) conversation;

    idgen = conv.getIDGenerator();
    String id = idgen.getID();

    KQML askMsg;
    if (msg.getContent() instanceof KQML) {
      askMsg = (KQML) msg.getContent();
      if (! askMsg.getPerformative().equalsIgnoreCase("ask-all")) {
	if (debug)
	  System.err.println(new Date() + 
	    " - kqml_travel_broker.doBrokerAll: borker-all contents is not ask-all. ");	
	try {
	  rtnMsg.setPerformative("sorry");
	  rtnMsg.setParameter(":sender", msg.getParameter(":receiver"));
	  rtnMsg.setParameter(":receiver", msg.getParameter(":sender"));
	  rtnMsg.setParameter(":in-reply-to", msg.getParameter(":reply-with"));
	  rtnMsg.setParameter(":reply-with", id);
	  rtnMsg.setParameter(":language", msg.getParameter(":language"));
	  rtnMsg.setParameter(":ontology", msg.getParameter(":ontology"));
	  rtnMsg.setContent("(:errmsg \"cannot handle broker-all " + 
			    askMsg.getPerformative() + "\")");
	} catch (Exception ex) {
	  ex.printStackTrace();
	}

	Conversation c = null;
	try {
	  c = km.sendMessage(rtnMsg);
	} catch (SendFailedException ex) {
	  ex.printStackTrace();
	} catch (InvalidFormatException ex) {
	  ex.printStackTrace();
	} catch (InvalidMessageSequenceException ex) {
	  ex.printStackTrace();
	} catch (JKQMLException ex) {
	  ex.printStackTrace();
	} 
	if (c == null) { 
	  System.err.println(new Date() + 
	    " < kqml_travel_broker.doBrokerAll(): sending response message failed");
	  return false;
	} else {
	  if (debug)
	    System.err.println(new Date() + 
	      " < kqml_travel_broker.doBrokerAll(): sent response message successfully");
	  return true;
	}
      }
    } else {
      if (debug)
	System.err.println(new Date() + 
	  " - kqml_travel_broker.doBrokerAll broker-all's content is not KQML. ");
      try {
	rtnMsg.setPerformative("sorry");
	rtnMsg.setParameter(":sender", msg.getParameter(":receiver"));
	rtnMsg.setParameter(":receiver", msg.getParameter(":sender"));
	rtnMsg.setParameter(":in-reply-to", msg.getParameter(":reply-with"));
	rtnMsg.setParameter(":reply-with", id);
	rtnMsg.setParameter(":language", msg.getParameter(":language"));
	rtnMsg.setParameter(":ontology", msg.getParameter(":ontology"));
	rtnMsg.setContent("(:errmsg \"broker-all's content is not KQML\" )");
      } catch (Exception ex) {
	ex.printStackTrace();
      }

      Conversation c = null;
      try {
	c = km.sendMessage(rtnMsg);
      } catch (SendFailedException ex) {
	ex.printStackTrace();
      } catch (InvalidFormatException ex) {
	ex.printStackTrace();
      } catch (InvalidMessageSequenceException ex) {
	ex.printStackTrace();
      } catch (JKQMLException ex) {
	ex.printStackTrace();
      } 

      if (c == null) { 
	System.err.println(new Date() + 
	  " < kqml_travel_broker.doBrokerAll(): sending response message failed");
	return false;
      } else {
	if (debug)
	  System.err.println(new Date() + 
	    " < kqml_travel_broker.doBrokerAll(): sent response message successfully");
	return true;
      }
    }
    
    // get expiration time from the content of ask-all
    Vector tokens = 
      ParseContent.parse((String)  askMsg.getContent());

    // default expiration time is 10 seconds
    String expirationTime = new String("10"); 

    for (int i=0; i < tokens.size(); i++) {
      if (((String) tokens.elementAt(i)).equalsIgnoreCase(":expirationTime")) {
	expirationTime = (String) tokens.elementAt(++i);
	if (debug)
	  System.err.println(new Date() + 
	    " - kqml_travel_broker.doBrokerAll parsing: expirationTime: " 
		+ expirationTime);
	continue;
      }
    }

    KQML rctMsg = new KQML(); // create recruit-all message
    try {
      rctMsg.setPerformative("recruit-all");
      rctMsg.setParameter(":sender", msg.getParameter(":receiver"));
      rctMsg.setParameter(":receiver", facilitator);
//    rctMsg.setParameter(":in-reply-to", msg.getParameter(":reply-with"));
      rctMsg.setParameter(":reply-with", id);
      rctMsg.setParameter(":language", "KQML");
      rctMsg.setParameter(":ontology", "kqml-ontology");
      rctMsg.setContent(askMsg);
    } catch (Exception ex) {
      ex.printStackTrace();
    }
//    Conversation c;
//    c = (Conversation) km.sendMessage(rctMsg);

    Conversation c = null;
    try {
      c = (Conversation) km.sendMessage(rctMsg);
    } catch (SendFailedException ex) {
      ex.printStackTrace();
    } catch (InvalidFormatException ex) {
      ex.printStackTrace();
    } catch (InvalidMessageSequenceException ex) {
      ex.printStackTrace();
    } catch (JKQMLException ex) {
      ex.printStackTrace();
    } 
    if (c == null) { 
      System.err.println(new Date() + 
	" < kqml_travel_broker.doBrokerAll(): sending response message failed");
      return false;
    } else {
      if (debug)
	System.err.println(new Date() + 
	   " < kqml_travel_broker.doBrokerAll(): sent response message successfully");
	// wait for result
      long waitmills = new Long(expirationTime).longValue() * 1000;
      long due = System.currentTimeMillis() + waitmills;
      long left;
      Vector flights = new Vector();
      StringBuffer content = new StringBuffer();

      if (debug) 
	System.err.println(new Date() + 
	  " - kqml_travel_broker.doBrokerAll(): waiting in " + expirationTime 
	  + " for response of recruit-all.");
      while ((left = due - System.currentTimeMillis()) > 0) {
	c.getResult().waitFor(left);
	if (c.getResult().isAvailable()) {
	  ReturnValue rtn = (ReturnValue) c.getResult().getSubscribedResult();
	  if (rtn.isOK()) {
	    if (rtn.getReturnValue() instanceof Vector) {
	      flights = (Vector) rtn.getReturnValue();
	      for (int i=0; i < flights.size(); i++) {
		FlightInfo flightInfo = (FlightInfo) flights.elementAt(i);
		if (debug)
		  System.err.println(new Date() + 
		    " - kqml_travel_broker.doBrokerAll(): got FlightInfo. "
		    + " making tell message");
		
		content.append(" :carrier ");
		content.append(flightInfo.getCarrier());
		content.append(" :flight ");
		content.append(flightInfo.getFlight());
		content.append(" :departure ");
		content.append("\"" + getAirPort(flightInfo.getDeparture()) + "\"");
		content.append(" :arrival ");
		content.append("\"" + getAirPort(flightInfo.getArrival()) + "\"");
		content.append(" :deptTime ");
		content.append("\"" + getTime(flightInfo.getDeptTime()) + "\"");
		content.append("\n");
		
	      }
	    }
	  }
	}
      }

      id = idgen.getID();
      if (content.length() != 0) {
	try {
	  rtnMsg.setPerformative("tell");
	  rtnMsg.setParameter(":sender", msg.getParameter(":receiver"));
	  rtnMsg.setParameter(":receiver", msg.getParameter(":sender"));
	  rtnMsg.setParameter(":in-reply-to", msg.getParameter(":reply-with"));
	  rtnMsg.setParameter(":reply-with", id);
	  rtnMsg.setParameter(":language", "anACL");
	  rtnMsg.setParameter(":ontology", "travel");
	  rtnMsg.setContent("("+ content + " )");
	} catch (Exception ex) {
	  ex.printStackTrace();
	}
      } else {
	if (debug) 
	  System.err.println(new Date() + 
	    " - kqml_travel_broker.doBrokerAll: No flight recieved.");
	try {
	  rtnMsg.setPerformative("sorry");
	  rtnMsg.setParameter(":sender", msg.getParameter(":receiver"));
	  rtnMsg.setParameter(":receiver", msg.getParameter(":sender"));
	  rtnMsg.setParameter(":in-reply-to", msg.getParameter(":reply-with"));
	  rtnMsg.setParameter(":reply-with", id);
	  rtnMsg.setParameter(":language", "anACL");
	  rtnMsg.setParameter(":ontology", "travel-broker");
	  rtnMsg.setContent("(:errmsg \" No flight found.\")");
	} catch (Exception ex) {
	  ex.printStackTrace();
	}
      }
      
//      c = (Conversation) km.sendMessage(rtnMsg);

      try {
	c = (Conversation) km.sendMessage(rtnMsg);
      } catch (SendFailedException ex) {
	ex.printStackTrace();
      } catch (InvalidFormatException ex) {
	ex.printStackTrace();
      } catch (InvalidMessageSequenceException ex) {
	ex.printStackTrace();
      } catch (JKQMLException ex) {
	ex.printStackTrace();
      } 
      if (c == null) { 
	System.err.println(new Date() + 
	  " < kqml_travel_broker.doBrokerAll: sending response message failed");
	return false;
      } else {
	if (debug)
	  System.err.println(new Date() + 
	    " < kqml_travel_broker.doBrokerAll: sent response message successfully");
	return true;
      }
    }
  }

  /**
   * Handles recruit-one performative.
   * 
   * @param conversation reference to the Conversation
   * @param msg KQML message
   * @return true if message is interpreted successfully, otherwise false.
   * 
   */
  protected boolean doRecruitOne(Conversation conversation, KQML msg) {
    if (debug) 
      System.err.println(new Date() + 
        " > kqml_travel_broker.doRecruitOne entered");

    KQML rtnMsg = new KQML();

    Conversation conv = (Conversation) conversation;
    idgen = conv.getIDGenerator();
    String id = idgen.getID();

    KQML subMsg = null; // subscribe message
    KQML askMsg = null; // ask-all message
    String errmsg = null;

    // error check
    if (msg.getContent() instanceof KQML) {
      subMsg = (KQML) msg.getContent(); 
      if (! subMsg.getPerformative().equalsIgnoreCase("subscribe")) {
	errmsg = new String("Content of the recruit-one is not subscribe. ");
      } else if (subMsg.getContent() instanceof KQML) {
	askMsg = (KQML) subMsg.getContent();
	if (! askMsg.getPerformative().equalsIgnoreCase("ask-all")) {
	  errmsg = new String("Content of subscribe of the recruit-one is not" 
          + " ask-all. ");
	} else {
	  // (recruit-one (subscribe (ask-all ..))) is OK.
	}
      } else {
	errmsg = new String("Content of subscribe of the recruit-one is not" 
			    + " KQML. ");
      }
    } else {
      errmsg = new String("Content of the recruit-one is not KQML");
    }

    if (errmsg != null) {
      if (debug)
	System.err.println(new Date() + 
	  " - kqml_travel_broker.doBrokerAll: borker-all contents is invalide: " 
	  + "reason: " + errmsg);