我必须通过蓝牙与arduino通信。 arduino连接到HC-06蓝牙模块，但这不是重点，因为我已经检查过（与Arduino的一些大师）蓝牙模块和配对。
因此，如您所知，当您将电脑配对蓝牙设备时，它可以为其分配几个COM端口。要通过蓝牙进行通信，您必须通过传出端口“发送消息”。我写了一个列出COM端口的小程序：第一次运行它时，我也可以看到传出端口。第二次，该COM端口将不会显示在列表中。显然你也无法连接到它。
有没有人知道发生了什么？这是我的（简单）代码，在许多教程中很常见。
java.util.Enumeration<CommPortIdentifier> portEnum = CommPortIdentifier.getPortIdentifiers();
while ( portEnum.hasMoreElements() )
{
CommPortIdentifier portIdentifier = portEnum.nextElement();
System.out.println(portIdentifier.getName());
}
我陷入困境并绝望，因为它似乎没有意义。
谢谢。 米歇尔
答案 0 :(得分：-1)
看看这个。 （摘自YOUTUBE。作者es Taha Emara）我做了一些修改，运行正常。
package serial_send;
//import gnu.io.CommPortIdentifier;
import gnu.io.CommPortIdentifier;
/**
*
* @author Administrador
*/
public class Test extends javax.swing.JFrame {
/**
* Creates new form Test
*/
public Test() {
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();
jComboBox1 = new javax.swing.JComboBox();
jTextField1 = new javax.swing.JTextField();
jButton2 = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jButton1.setText("puertos disponibles");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "", "", "", "" }));
jComboBox1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jComboBox1ActionPerformed(evt);
}
});
jButton2.setText("enviar");
jButton2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton2ActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap(123, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, 194, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 180, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(83, 83, 83))
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
.addComponent(jTextField1)
.addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, 152, Short.MAX_VALUE))
.addGap(112, 112, 112))))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(29, 29, 29)
.addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 33, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(30, 30, 30)
.addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 57, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(34, 34, 34)
.addComponent(jButton2)
.addContainerGap(56, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
java.util.Enumeration<CommPortIdentifier> portEnum = CommPortIdentifier.getPortIdentifiers();
int i = 0;
String[] r = new String[25];
while (portEnum.hasMoreElements() && i < 20) {
CommPortIdentifier portIdentifier = portEnum.nextElement();
r[i] = portIdentifier.getName();//+ " - " + getPortTypeName(portIdentifier.getPortType()) ;
System.out.println("i= " + i);
i++;
}
jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(r));
}
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
String x = jTextField1.getText();
Serial sr = new Serial();
Object selectedItem = jComboBox1.getSelectedItem();
String com = selectedItem.toString();
sr.ser(x.getBytes(), com);
sr.close();
}
private void jComboBox1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
/**
* @param args the command line arguments
*/
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 | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Test.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new Test().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JComboBox jComboBox1;
private javax.swing.JTextField jTextField1;
// End of variables declaration
}