1、下載java Communications api開發包。
2、將win32com.dll拷貝入C:\j2sdk1.4.2_04\bin

3、將comm.jar拷貝入C:\j2sdk1.4.2_04\jre\lib\ext

4、將javax.comm.properties拷貝入C:\j2sdk1.4.2_04\jre\lib

public static void main(String[] args) {
            CommPortIdentifier portId;
            Enumeration en = CommPortIdentifier.getPortIdentifiers();
            // iterate through the ports.
            while (en.hasMoreElements()) {
                portId = (CommPortIdentifier) en.nextElement();
                if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
                    System.out.println(portId.getName());
                }
            }
       
 }

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