这是我们为 Java GUI 实现的代码。问题是，由于串行数据是以位读取的，我们似乎无法想出一种方法来分离来自三个不同传感器（三个LM35温度传感器作为占位符）的数据。问题在于 serialevent 类。
import gnu.io.*;
import java.awt.Color;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Scanner;
import java.util.TooManyListenersException;
public class Communicator implements SerialPortEventListener
{
//Passed from main GUI.
GUI window = null;
//For containing the ports that will be found.
private Enumeration ports = null;
//map the port names to CommPortIdentifiers
private HashMap portMap = new HashMap();
//This is the object that contains the opened port.
private CommPortIdentifier selectedPortIdentifier = null;
private SerialPort serialPort = null;
//Input and output streams for sending and receiving data.
private InputStream input = null;
private OutputStream output = null;
//Just a boolean flag that I use for enabling
//and disabling buttons depending on whether the program
//is connected to a serial port or not.
private boolean bConnected = false;
//The timeout value for connecting with the port.
final static int TIMEOUT = 2000;
//Some ASCII values for for certain things.
final static int SPACE_ASCII = 32;
final static int DASH_ASCII = 45;
final static int NEW_LINE_ASCII = 10;
//A string for recording what goes on in the program;
//this string is written to the GUI.
String logText = "";
public Communicator(GUI window)
{
this.window = window;
}
//Search for all the serial ports
// Pre: none
// Post: adds all the found ports to a combo box on the GUI
public void searchForPorts()
{
ports = CommPortIdentifier.getPortIdentifiers();
while (ports.hasMoreElements())
{
CommPortIdentifier curPort = (CommPortIdentifier)ports.nextElement();
//Get only serial ports
if (curPort.getPortType() == CommPortIdentifier.PORT_SERIAL)
{
window.cboxPorts.addItem(curPort.getName());
portMap.put(curPort.getName(), curPort);
}
}
}
//Connect to the selected port in the combo box
// Pre : ports are already found by using the searchForPorts method
// Post: the connected communications port is stored in commPort, otherwise,
// an exception is generated
public void connect()
{
String selectedPort = (String)window.cboxPorts.getSelectedItem();
selectedPortIdentifier = (CommPortIdentifier)portMap.get(selectedPort);
CommPort commPort = null;
try
{
//The method below returns an object of type CommPort
commPort = selectedPortIdentifier.open("TigerControlPanel", TIMEOUT);
//The CommPort object can be casted to a SerialPort object
serialPort = (SerialPort)commPort;
//For controlling GUI elements
setConnected(true);
//Logging
logText = selectedPort + " opened successfully.";
window.txtLog.setForeground(Color.black);
window.txtLog.append(logText + "\n");
window.txtLog1.setForeground(Color.black);
window.txtLog1.append(logText + "\n");
window.txtLog2.setForeground(Color.black);
window.txtLog2.append(logText + "\n");
//CODE ON SETTING BAUD RATE, ETC. OMITTED
//XBEE PAIR IS ASSUMED TO HAVE THE SAME SETTINGS ALREADY
//Enables the controls on the GUI if a successful connection is made
window.keybindingController.toggleControls();
}
catch (PortInUseException e)
{
logText = selectedPort + " is in use. (" + e.toString() + ")";
window.txtLog.setForeground(Color.RED);
window.txtLog.append(logText + "\n");
window.txtLog1.setForeground(Color.RED);
window.txtLog1.append(logText + "\n");
window.txtLog2.setForeground(Color.RED);
window.txtLog2.append(logText + "\n");
}
catch (Exception e)
{
logText = "Failed to open " + selectedPort + "(" + e.toString() + ")";
window.txtLog.append(logText + "\n");
window.txtLog.setForeground(Color.RED);
window.txtLog1.append(logText + "\n");
window.txtLog1.setForeground(Color.RED);
window.txtLog2.append(logText + "\n");
window.txtLog2.setForeground(Color.RED);
}
}
//Open the input and output streams
// pre: an open port
// post: initialized intput and output streams for use to communicate data
public boolean initIOStream()
{
//Return value for whather opening the streams is successful or not
boolean successful = false;
try {
input = serialPort.getInputStream();
output = serialPort.getOutputStream();
successful = true;
return successful;
}
catch (IOException e) {
logText = "I/O Streams failed to open. (" + e.toString() + ")";
window.txtLog.setForeground(Color.red);
window.txtLog.append(logText + "\n");
window.txtLog1.setForeground(Color.red);
window.txtLog1.append(logText + "\n");
window.txtLog2.setForeground(Color.red);
window.txtLog2.append(logText + "\n");
return successful;
}
}
//Starts the event listener that knows whenever data is available to be read
// pre: an open serial port
// post: an event listener for the serial port that knows when data is recieved
public void initListener()
{
try
{
serialPort.addEventListener(this);
serialPort.notifyOnDataAvailable(true);
}
catch (TooManyListenersException e)
{
logText = "Too many listeners. (" + e.toString() + ")";
window.txtLog.setForeground(Color.red);
window.txtLog.append(logText + "\n");
window.txtLog1.setForeground(Color.red);
window.txtLog1.append(logText + "\n");
window.txtLog2.setForeground(Color.red);
window.txtLog2.append(logText + "\n");
}
}
//Disconnect the serial port
// pre : an open serial port
// post: clsoed serial port
public void disconnect()
{
//Close the serial port
try
{
serialPort.removeEventListener();
serialPort.close();
input.close();
output.close();
setConnected(false);
window.keybindingController.toggleControls();
logText = "Disconnected.";
window.txtLog.setForeground(Color.red);
window.txtLog.append(logText + "\n");
window.txtLog1.setForeground(Color.red);
window.txtLog1.append(logText + "\n");
window.txtLog2.setForeground(Color.red);
window.txtLog2.append(logText + "\n");
}
catch (Exception e)
{
logText = "Failed to close " + serialPort.getName() + "(" + e.toString() + ")";
window.txtLog.setForeground(Color.red);
window.txtLog.append(logText + "\n");
window.txtLog1.setForeground(Color.red);
window.txtLog1.append(logText + "\n");
window.txtLog2.setForeground(Color.red);
window.txtLog2.append(logText + "\n");
}
}
final public boolean getConnected()
{
return bConnected;
}
public void setConnected(boolean bConnected)
{
this.bConnected = bConnected;
}
//What happens when data is received
// pre : serial event is triggered
// post: processing on the data it reads
public void serialEvent(SerialPortEvent evt) {
if (evt.getEventType() == SerialPortEvent.DATA_AVAILABLE)
{
try
{
byte singleData = (byte)input.read();
//byte[] buffer = new byte[128];
if (singleData != NEW_LINE_ASCII)
{
logText = new String(new byte[] {singleData});
window.txtLog.append(logText);
}
else
{
window.txtLog.append("\n");
}
}
catch (Exception e)
{
logText = "Failed to read data. (" + e.toString() + ")";
window.txtLog.setForeground(Color.red);
window.txtLog.append(logText + "\n");
}
}
}
//Method that can be called to send data
// pre : open serial port
// post: data sent to the other device
}