/**
* Copyright (c) 2013, Institute of Information Systems (Sven Groppe and contributors of LUPOSDATE), University of Luebeck
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this list of conditions and the following
* disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other materials provided with the distribution.
* - Neither the name of the University of Luebeck nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package lupos.event.producer;
import java.io.IOException;
import java.io.Serializable;
import java.net.URISyntaxException;
import java.util.*;
import javax.swing.JOptionPane;
import lupos.datastructures.items.Triple;
import lupos.datastructures.items.literal.Literal;
import lupos.datastructures.items.literal.LiteralFactory;
import lupos.event.communication.ConnectionRequest;
import lupos.event.communication.IDisconnectedHandler;
import lupos.event.communication.IMessageReceivedHandler;
import lupos.event.communication.SerializedTriple;
import lupos.event.communication.SerializingMessageService;
import lupos.event.communication.TcpConnectInfo;
import lupos.event.communication.TcpMessageTransport;
import lupos.event.util.Literals;
/**
* Base class for producers.
*
*/
public abstract class ProducerBase implements IMessageReceivedHandler<Serializable>, IDisconnectedHandler {
public static int MIN_INTERVAL = 100;
private final Literal TIMESTAMP_LITERAL = LiteralFactory.createURILiteralWithoutException("<timestamp>");
private final SerializingMessageService msgService;
private TcpConnectInfo connectingSubBroker;
private final int interval;
/**
*
* @param msgService The message service that the producer should use to communicate.
* @param interval Interval in milliseconds
*/
public ProducerBase(SerializingMessageService msgService, int interval) {
this.msgService = msgService;
this.interval = interval;
// register message listener
msgService.addHandler2(this);
msgService.addDisconnectHandler(this);
}
/**
* Starts the producer. {@link produce}
*/
public void start() {
try {
while (true) {
long startTime = System.currentTimeMillis();
// produce triples (implemented in subclasses)
List<List<Triple>> triples = produce();
if (triples != null && !triples.isEmpty()) {
// adds timestamp triple if not existent
List<List<Triple>> timestampedTriples = addTimestampTriples(triples);
// use one message per event:
for(List<Triple> listOfTriples: timestampedTriples){
// serialize triples
ArrayList<SerializedTriple> serializedTriples = serializeTriples(listOfTriples);
// send triples to broker
this.msgService.sendMessage(serializedTriples);
}
} else {
// ignore!
// System.out.println("Producer.produce returned null");
System.out.print(".");
}
waitForEndOfInterval(startTime);
}
} catch (Exception e) {
System.err.println(e);
e.printStackTrace();
}
}
private void waitForEndOfInterval(long startTime) throws InterruptedException {
long elapsedTime = this.interval - (System.currentTimeMillis() - startTime);
if(elapsedTime>0){
Thread.sleep(elapsedTime);
}
}
private List<List<Triple>> addTimestampTriples(List<List<Triple>> triples) throws URISyntaxException {
List<List<Triple>> triples2 = new ArrayList<List<Triple>>();
for(List<Triple> listOfTriples: triples){
triples2.add(this.addTimestampTriple(listOfTriples));
}
return triples2;
}
/**
* Adds a timestamp triple to a list of triples, if it doesn't contain one.
* @param triples
* @throws URISyntaxException
*/
private List<Triple> addTimestampTriple(List<Triple> triples) throws URISyntaxException {
for(Triple t : triples) {
if(0 == this.TIMESTAMP_LITERAL.compareToNotNecessarilySPARQLSpecificationConform(t.getPredicate())){
return triples;
}
}
long timestamp = System.currentTimeMillis() / 1000;
Literal obj = Literals.createTyped(timestamp+"", Literals.XSD.LONG);
Triple timestampTriple = new Triple(triples.get(0).getSubject(), this.TIMESTAMP_LITERAL, obj);
List<Triple> triples2 = new ArrayList<Triple>(triples);
triples2.add(timestampTriple);
return triples2;
}
private ArrayList<SerializedTriple> serializeTriples(List<Triple> triples) throws IOException {
ArrayList<SerializedTriple> l = new ArrayList<SerializedTriple>();
for(Triple t : triples)
l.add(new SerializedTriple(t));
return l;
}
protected static List<List<Triple>> fold(List<Triple> triplesToFold){
List<List<Triple>> result = new LinkedList<List<Triple>>();
result.add(triplesToFold);
return result;
}
public abstract List<List<Triple>> produce();
protected static String askForHostOfBroker(){
return JOptionPane.showInputDialog("Enter the host of the broker:", "localhost");
}
/**
* Establishes a connection to the master broker
* and afterwards send a connection request message to it
* @return msgService the message service of the connection
*/
protected static SerializingMessageService connectToMaster(){
// create communication channel
SerializingMessageService msgService = null;
try {
msgService = new SerializingMessageService(TcpMessageTransport.class);
msgService.connect(new TcpConnectInfo(JOptionPane.showInputDialog("Enter the host IP adress of the MasterBroker:", "localhost"), Integer.parseInt(JOptionPane.showInputDialog("Enter the host port of the MasterBroker:", "4444"))));
msgService.sendMessage(new ConnectionRequest(ConnectionRequest.REQUESTTYPE_PRODUCER));
} catch (Exception e) {
e.printStackTrace();
}
return msgService;
}
@Override
public void messageReceived(Object src, Serializable msg){
if (msg instanceof TcpConnectInfo){
this.connectingSubBroker = (TcpConnectInfo)msg;
this.msgService.disconnect();
}
}
/**
* This method will be called after the master
* broker has sent a forwarding tcpConnect object.
* This method will then connect to this specific
* subbroker
*/
@Override
public void disconnected(){
// Connect to the sub broker when disconnected
// which should only occur on handshake
try {
this.msgService.connect(this.connectingSubBroker);
ConnectionRequest conReq = new ConnectionRequest(ConnectionRequest.REQUESTTYPE_PRODUCER);
conReq.setPort(TcpMessageTransport.SERVER_PORT);
this.msgService.sendMessage(conReq);
} catch (Exception e) {
e.printStackTrace();
}
}
}