/Java/OPSJLib/src/ops/Manager.java

/**

*

* Copyright (C) 2006-2009 Anton Gravestam.

*

* This file is part of OPS (Open Publish Subscribe).

*

* OPS (Open Publish Subscribe) is free software: you can redistribute it and/or modify

* it under the terms of the GNU Lesser General Public License as published by

* the Free Software Foundation, either version 3 of the License, or

* (at your option) any later version.



* OPS (Open Publish Subscribe) is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

* GNU Lesser General Public License for more details.

*

* You should have received a copy of the GNU Lesser General Public License

* along with OPS (Open Publish Subscribe).  If not, see <http://www.gnu.org/licenses/>.

*/



package ops;



import java.io.IOException;

import java.net.DatagramPacket;

import java.net.InetAddress;

import java.net.MulticastSocket;

import java.net.UnknownHostException;

import java.util.TreeMap;

import java.util.Vector;

import ops.*;



/**

 *

 * @author Anton

 */

public class Manager implements Runnable

{

    private static Manager theManager;

    

    

    public static int MAX_SIZE = 65000;

    public static int MANAGER_PORT = 14000;

    public static int TOPIC_BASE_PORT = 14001;

    public static String handShake =":-) ";

    

    

    private MulticastSocket multicastSocket;

    

    private Vector<Topic> topics = new Vector<Topic>();

    

    private byte[] readBytes;

    

    private Thread thread;

    

    /** Creates a new instance of Manager */

    private Manager()

    {

        try

        {

            multicastSocket = new MulticastSocket(MANAGER_PORT);

            multicastSocket.joinGroup(InetAddress.getByName("235.5.5.5"));

            sendHandShake();

        }

        catch (UnknownHostException ex)

        {

            ex.printStackTrace();

        }

        catch (IOException ex)

        {

            ex.printStackTrace();

        }

        

        thread = new Thread(this);

        thread.start();

        try

        {

            System.out.println("Handshaking...");

            Thread.sleep(1000);

            System.out.println("Handshaking done.");

        }

        catch (InterruptedException ex)

        {

            ex.printStackTrace();

        }

        

    }

    public int getTopicPort(String topicKey)

    {

        for (Topic t : topics)

        {

            if(t.getName().equals(topicKey))

                return t.getPort();

            

        }

        return -1;

    }

    

    //By singelton pattern

    public static Manager getManager()

    {

        if(theManager == null)

            theManager = new Manager();

        

        return theManager;

    }

    

    public void run()

    {

        while(true)

        {

            

            readBytes = new byte[Manager.MAX_SIZE];

            

            DatagramPacket p = new DatagramPacket(readBytes, Manager.MAX_SIZE);

            try

            {

                multicastSocket.receive(p);

                

                String s = new String(p.getData());

                String[] sArray = s.split(" ");

                

                if(sArray[0].equals(":-)"))

                {

                    sendTopics();

                }

                else if(sArray[0].equals("&"))

                {

                    

                    

                    if(getTopicPort(sArray[1]) == -1)

                    {

                        //topics.add(new Topic(sArray[1], Integer.parseInt(sArray[2])));

                        System.out.println("Topic " + sArray[1] + " updated at port " + getTopicPort(sArray[1]));

                        

                    }

                    

                }

                else

                {

                    

                    if(getTopicPort(sArray[0]) != -1)

                    {

                        System.out.println("Topic " + sArray[0] + " found at port " + getTopicPort(sArray[0]));

                    }

                    else

                    {

                        //topics.add(new Topic(sArray[0], TOPIC_BASE_PORT + topics.size()));

                        System.out.println("Topic " + sArray[0] + " registered at port " + (TOPIC_BASE_PORT + topics.size()-1));

                    }

                }

                

            }

            catch (IOException ex)

            {

                ex.printStackTrace();

            }

            catch (ArrayIndexOutOfBoundsException e)

            {

                System.out.println("Topic refused");

                e.printStackTrace();

                

            }

        }

    }

    

    private void sendHandShake()

    {

        

        try

        {

            multicastSocket.send(new DatagramPacket(handShake.getBytes(), handShake.length(),InetAddress.getByName("235.5.5.5"),Manager.MANAGER_PORT));

        }

        catch (IOException ex)

        {

            ex.printStackTrace();

        }

    }

    private void sendTopics()

    {

        for(Topic t : topics)

        {

            String message = "& " + t.getName() + " " + t.getPort() + " ";

            

            try

            {

                multicastSocket.send(new DatagramPacket(message.getBytes(), message.length(),InetAddress.getByName("235.5.5.5"),Manager.MANAGER_PORT));

            }

            catch (IOException ex)

            {

                ex.printStackTrace();

            }

        }

        

    }

    

    public void registerSubscriber(String topic)

    {

        if(getTopicPort(topic) == -1)

        {

            registerTopic(topic);

        }

    }

    public void registerPublisher(String topic)

    {

        if(getTopicPort(topic) == -1)

        {

            registerTopic(topic);

        }

    }

    

    

    private void registerTopic(String topic)

    {

        try

            {

                multicastSocket = new MulticastSocket(Manager.MANAGER_PORT);

                multicastSocket.joinGroup(InetAddress.getByName("235.5.5.5"));

            }

            catch (UnknownHostException ex)

            {

                ex.printStackTrace();

            }

            catch (IOException ex)

            {

                ex.printStackTrace();

            }

            

            String managerString = topic + " " + "TestClass" + " ";//data.getClass().getName();

            try

            {

                multicastSocket.send(new DatagramPacket(managerString.getBytes(), managerString.length(),InetAddress.getByName("235.5.5.5"),Manager.MANAGER_PORT));

            }

            catch (IOException ex)

            {

                ex.printStackTrace();

            }

    }

    

}