WalkerSource.java

/*
 * Created on Feb 5, 2004
 *
 * A RBNB source that generates numbers in a bounded random walk.
 */

package org.nees.rbnb;
 
import com.rbnb.sapi.*;
import COM.Creare.Utility.ArgHandler; //for argument parsing
import COM.Creare.Utility.RBNBProcess; //alternative to System.exit, so
                                       //don't bring down servlet engine

public class WalkerSource {

    SimpleRandomWalk base = new SimpleRandomWalk();
    
    private static final String SERVER = "localhost:3333";
    private static final String SOURCE_NAME = "RandomWalk";
    private static final String CHANNEL_NAME = "RandomWalkData";
    private static final long TIMER_INTERVAL=1000;
    
    private String server = SERVER;
    private String sourceName = SOURCE_NAME;
    private String channelName = CHANNEL_NAME;
    private long timerInterval = TIMER_INTERVAL;
     
    Source source = null;
    ChannelMap sMap;
    int index;
    boolean connected = false;
    
    Thread timerThread;
    boolean runit = false;
    
    public static void main(String[] args) {
        WalkerSource w = new WalkerSource(args);
        w.exec();
        w.startThread();
    }
    
    private void printUsage() {
        System.out.println("WalkerSource: usage is...");        
        System.out.print("WalkerSource ");
        System.out.print("[-s server_hostname *" + SERVER + "] ");
        System.out.print("[-n source_name *" + SOURCE_NAME + "] ");
        System.out.print("[-c channel_name *" + CHANNEL_NAME + "] ");
        System.out.print("[-t timer_interval *" + TIMER_INTERVAL + "]");
        System.out.println();
    }
    
    public WalkerSource(String[] args) {
        //parse args
        try {
            ArgHandler ah=new ArgHandler(args);
            if (ah.checkFlag('h')) {
                printUsage();
                RBNBProcess.exit(0);                
            }
            if (ah.checkFlag('s')) {
                String a=ah.getOption('s');
                if (a!=null) server=a;
            }
            if (ah.checkFlag('n')) {
                String a=ah.getOption('n');
                if (a!=null) sourceName=a;
            }
            if (ah.checkFlag('c')) {
                String a=ah.getOption('c');
                if (a!=null) channelName=a;
            }
            if (ah.checkFlag('t')) {
                String a=ah.getOption('t');
                if (a!=null) timerInterval=Long.parseLong(a);
            }
        } catch (Exception e) {
            System.err.println("WalkerSource argument exception "+e.getMessage());
            e.printStackTrace();
            RBNBProcess.exit(0);
        }
        
        System.out.println("Starting WalkerSource on " + server + " as " + sourceName);
        System.out.println("  Channel name = " + channelName + "; timer interval = " + timerInterval);
        System.out.println("  Use WalkerSource -h to see optional parameters");
    }
    
    public WalkerSource(String server_host, String source_name, String channel_name,
        long timer_interval)
    {
        server = server_host;
        sourceName = source_name;
        channelName = channel_name;
        timerInterval = timer_interval;

        System.out.println("Starting WalkerSource on " + server + " as " + sourceName);
        System.out.println("  Channel name = " + channelName + "; timer interval = " + timerInterval);
        System.out.println("  Use WalkerSource -h to see optional parameters");
    }
    
    public WalkerSource()
    {
        this(SERVER,SOURCE_NAME,CHANNEL_NAME,TIMER_INTERVAL);
    }
    
    public void exec()
    {
        try {
            // Create a source and connect:
            source=new Source();
            source.OpenRBNBConnection(server,sourceName);
            sMap = new ChannelMap();
            int index = sMap.Add(channelName);
            connected = true;
            System.out.println("WalkerSource: Connection made to sever = "
                + server + " as " + sourceName + " with " + channelName + ".");
        } catch (SAPIException se) { se.printStackTrace(); }
    }
    
    public void startThread()
    {
        
        if (!connected) return;
        
        // Use this inner class to hide the public run method
        Runnable r = new Runnable() {
            public void run() {
              runWork();
            }
        };
        runit = true;
        timerThread = new Thread(r, "Timer");
        timerThread.start();
        System.out.println("WalkerSource: Started thread.");
    }

    public void stopThread()
    {
        if (!connected) return;
        
        runit = false;
        timerThread.interrupt();
        System.out.println("WalkerSource: Stopped thread.");
    }
    
    private void runWork ()
    {
        try {
            while(connected && runit)
            {
                // Push data onto the server:
                // System.out.print("Put new data to server: ");
                sMap.PutTimeAuto("timeofday");
                double data[] = new double[1];
                data[0] = base.next();
                sMap.PutDataAsFloat64(index,data);
                // System.out.println("" + data[0]);
                source.Flush(sMap);
                Thread.sleep(timerInterval);
            }
        } catch (SAPIException se) {
            se.printStackTrace(); 
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        timerThread = null;
    }
    
    public boolean isRunning()
    {
        return (connected && runit);
    }
}

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