我尝试使用串口在我的PC（使用Netbeans和RXTX的Windows 7）之间进行通信。我有一个串行事件的问题（public void serialEvent（SerialPortEvent arg0））。此事件应该重新获取数据并将其写入标签（jLabel1.setText（＆＃34; sfazds＆＃34;））。不幸的是，这个事件不会改变标签文本，我现在不知道为什么。以下是我的代码：
import gnu.io.CommPort;
import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;
import gnu.io.SerialPortEvent;
import gnu.io.SerialPortEventListener;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class RS extends javax.swing.JFrame implements SerialPortEventListener{
static OutputStream out;
static InputStream in;
public RS() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jButton1 = new javax.swing.JButton();
jLabel1 = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
addWindowListener(new java.awt.event.WindowAdapter() {
public void windowOpened(java.awt.event.WindowEvent evt) {
formWindowOpened(evt);
}
});
jButton1.setText("jButton1");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
jLabel1.setText("jLabel1");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(54, 54, 54)
.addComponent(jButton1))
.addGroup(layout.createSequentialGroup()
.addGap(203, 203, 203)
.addComponent(jLabel1)))
.addContainerGap(217, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(21, 21, 21)
.addComponent(jButton1)
.addGap(34, 34, 34)
.addComponent(jLabel1)
.addContainerGap(222, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
byte[] b = new byte[2];
b[0] = 'a';
b[1] = 'b';
try{
out.write(b);
}
catch(Exception e){
e.printStackTrace();
}
}
private void formWindowOpened(java.awt.event.WindowEvent evt) {
try{
(new RS()).connect("COM3");
}
catch(Exception e){
e.printStackTrace();
}
}
void connect(String portName) throws Exception{
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
if (portIdentifier.isCurrentlyOwned()){
JOptionPane.showMessageDialog(null, "Błąd: Port jest obecnie w użyciu");
}
else{
CommPort commPort = portIdentifier.open(this.getClass().getName(), 2000);
if (commPort instanceof SerialPort){
SerialPort serialPort = (SerialPort) commPort;
serialPort.setSerialPortParams(57600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
in = serialPort.getInputStream();
out = serialPort.getOutputStream();
(new Thread(new SerialWriter(out))).start();
serialPort.addEventListener(this);
serialPort.notifyOnDataAvailable(true);
}
else{
JOptionPane.showMessageDialog(null, "Tylko port szeregowy może być podłączony!");
}
}
}
@Override
public void serialEvent(SerialPortEvent arg0) {
int data;
byte[] buffer = new byte[1024];
try{
int len = 0;
while ( ( data = in.read()) > -1 ){
if ( data == '\n' ) {
break;
}
buffer[len++] = (byte) data;
}
System.out.print(new String(buffer,0,len));
jLabel1.setText("sfazds");
JOptionPane.showMessageDialog(null, new String(buffer,0,len));
}
catch ( IOException e ){
System.exit(-1);
}
}
public static class SerialWriter implements Runnable{
OutputStream out;
public SerialWriter(OutputStream out){
this.out = out;
}
@Override
public void run(){
try{
int c = 0;
while ((c = System.in.read()) > -1){
this.out.write(c);
}
}
catch(IOException e){
System.exit(-1);
}
}
}
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(RS.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(RS.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(RS.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(RS.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new RS().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JLabel jLabel1;
// End of variables declaration
}
答案 0 :(得分：1)
您的输出可能与EventDispatcherTread未同步。请尝试以下方法：
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
jLabel1.setText("sfazds");
}
});