stdgpstest.java

A Java Framework for connecting to and exchanging data from GPS units to J2ME Mobile Devices. Serial

package com.libGPS4j2me.examples;

// J2ME
import javax.microedition.io.CommConnection;
import javax.microedition.io.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;

// J2SE
import javax.bluetooth.*;
import com.libGPS4j2me.*;
import java.util.Enumeration;
import java.util.Vector;
import java.io.*;

// libGPS4j2me
import com.libGPS4j2me.devices.StdGPS.*;
import com.libGPS4j2me.GPS;
import com.libGPS4j2me.io.bt.*;

/**
 * A simple test-program that queries the GPS for a description of itself. <br/>
 * A good way to initially test the connection to the GPS. <br/>Attempts to
 * turn off the GPS after retrieving the description.
 */

public class StdGPSTest extends MIDlet implements Runnable, IGPSlistener,
        StdGPSListener, CommandListener
{

	/*
	 * The url connection string
	 */
	private String BT_url;

	/**
	 * The GPS unit
	 */
	private GPS gps;

	//Define UI CMDs
	private Command exitCommand;
	private Command pauseCommand;
	private Command resumeCommand;

        // Define UIs
	private Display display;
	private Canvas canvas;
	private Form screen;

	private static final long BREAK = 3000;
	private Thread runner;
	private boolean isTransferComplete;

	public StdGPSTest() {

		// Manage CMDs
		exitCommand = new Command("Exit", Command.SCREEN, 0);
		pauseCommand = new Command("Pause", Command.SCREEN, 2);
		resumeCommand = new Command("Resume", Command.SCREEN, 2);
		// Manage UI
		display = Display.getDisplay(this);
		screen = new Form("Bluetooth-GPS Device Test");
		screen.addCommand(exitCommand);
		screen.addCommand(pauseCommand);
		screen.addCommand(resumeCommand);
		screen.setCommandListener(this);

		isTransferComplete = false;
	}

	//MIDlet Life Cycle
	protected void startApp() {

		// start bluetooth devices search
		canvas = new BTCanvas(this);
		// set current UI
		display.setCurrent(canvas);
	}

	protected void pauseApp() {
	}

	protected void destroyApp(boolean unconditional) {
            // stop this and gps unit
            stop();
            gps.shutdown(true);
        }

	public void commandAction(Command c, Displayable s) {
            if (c == exitCommand) {
                destroyApp(false);
                notifyDestroyed();
            }
            else if(c == pauseCommand) {
                stop();
            }
            else if(c == resumeCommand) {
                stop();
                start();
            }
        }

       public void run() {

            // set current UI
            display.setCurrent(screen);
			// get selected BT device url
            BT_url = BTConnector.url;

			System.out.println("Connecting to GPS...");
            //connect to GPS unit by BT_url
            gps = new StdGPS(BT_url);
            //add listeners
            ((StdGPS) gps).addGPSlistener(this);
            ((StdGPS) gps).addStdGPSListener(this);

            System.out.println("Starting GPS...");
            //Start reading from GPS
            ((StdGPS) gps).start();
			waitForResponse();

			System.out.println("Waiting...");
			try {
					Thread.sleep(BREAK);
			   	} catch (InterruptedException e1) {
			    	e1.printStackTrace();
         	}

			System.out.println("Shutting down...");
           	// Disconnect from GPS
           	//((StdGPS) gps).shutdown(true);
        }

       /** Wait for transfer completed */
       private void waitForResponse() {
            //wait for GPS response
            System.out.println("Waiting for GPS...");
            while (!isTransferComplete) {
                    try {
                            Thread.sleep(BREAK);
                    } catch (InterruptedException e1) {
                            e1.printStackTrace();
                    }
            }
            isTransferComplete = false;
	}

    /** Start a new thread if not started yet.*/
	public void start() {
            if (runner == null) {
                runner = new Thread(this);
                runner.start();
            }
	}

	/** Stop this thread. */
        public void stop() {
            runner = null;
            ((StdGPS) gps).shutdown(true);
	}

	/** This method will be called for each sentence received from the GPS. */
	public void DataRecordReceived(DataRecord r) {
            isTransferComplete = true;
            System.out.println("NMEA Record data received:\n" + r.toString());
        }

        /** Invoked when the GPS transmits time-data.*/
        public void timeReceived(ITime t) {
			TimeDataRecord td = (TimeDataRecord) t;
            isTransferComplete = true;
            System.out.println("NMEA Time data received:\n" + td.toString());
        }

        /** Invoked when the GPS transmits date-data.*/
	public void dateReceived(IDate d) {
			TimeDataRecord td = (TimeDataRecord) d;
            isTransferComplete = true;
            System.out.println("NMEA Date data received:\n" + td.toString());
        }

        /** Invoked when the GPS transmits position-data.*/
	public void positionReceived(IPosition pos) {
            PositionDataRecord p = (PositionDataRecord) pos;
            isTransferComplete = true;
            System.out.println("NMEA Position data received:\n" + p.toString());
	}
}