import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.TooManyListenersException;

import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;
import gnu.io.SerialPortEvent;
import gnu.io.SerialPortEventListener;
import gnu.io.UnsupportedCommOperationException;


public class SerialWork implements SerialPortEventListener{

    /**
     * @param args
     */
    public static void main(String[] args) {
        listPorts();
        // example Arduino connection
       // new SerialWork("/dev/cu.usbserial-A2002nGt", 9600);
        
        // example SunSPOT connection
        new SerialWork("/dev/cu.usbmodem0000103D1", 9600);
        
    }

    SerialPort mySerialPort;
    InputStream in;
    OutputStream out;
    
    public SerialWork(String whichPort, int whichSpeed) {
        //which port you want to use and the baud come in as parameters

        try {
            //find the port
            CommPortIdentifier portId = CommPortIdentifier.getPortIdentifier(whichPort);
            //open the port
            mySerialPort = (SerialPort)portId.open("my_java_serial" + whichPort, 2000);
            //configure the port
            try {
                    mySerialPort.setSerialPortParams(whichSpeed,
                    mySerialPort.DATABITS_8,
                    mySerialPort.STOPBITS_1,
                    mySerialPort.PARITY_NONE);
            } catch (UnsupportedCommOperationException e){System.out.println("Probably an unsupported Speed");}
            //establish streams for reading and writing to the port
            try {
                in = mySerialPort.getInputStream();
                out = mySerialPort.getOutputStream();
            } catch (IOException e) { System.out.println("couldn't get streams");}

            
            // we could read from "in" in a separate thread, but the API gives us events
            try {
                mySerialPort.addEventListener(this);
                mySerialPort.notifyOnDataAvailable(true);
            } catch (TooManyListenersException e) {System.out.println("couldn't add listener");}
        }
        catch (Exception e) { System.out.println("Port in Use: "+e);}

    }

    byte[] buffer= new byte[1024];
    
    public void serialEvent(SerialPortEvent event) {
        if (event.getEventType()== SerialPortEvent.DATA_AVAILABLE) {
            try {
                // we could use in.available() to see whether we have enough data
                //System.out.println(Integer.toBinaryString(in.read()));
                int length= in.available();
                length=  length<1024?length: 1024;
                in.read(buffer, 0, length);
                System.out.write(buffer, 0, length);
            } catch (IOException e) {}
        } 
    }

    public static void listPorts(){
        Enumeration portList = CommPortIdentifier.getPortIdentifiers();
        while (portList.hasMoreElements()) {
            CommPortIdentifier portId = (CommPortIdentifier)portList.nextElement();
            if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL){
                System.out.println(portId.getName() + " " +portId.getCurrentOwner());
            }   
        }
    }
}