CommPortIdentifier portId;
        Enumeration en = CommPortIdentifier.getPortIdentifiers();
        // iterate through the ports.
        while(en.hasMoreElements()) {
            portId = (CommPortIdentifier) en.nextElement();
            System.out.println(portId.getName());
            if(portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
                System.out.println(portId.getName());
            }
        }

        portId = CommPortIdentifier.getPortIdentifier("COM1");
        SerialPort sPort = (SerialPort) portId.open("串口所有者名称", 1000);
        System.out.println("start-----------");
        final InputStream is = sPort.getInputStream();
        sPort.addEventListener(new SerialPortEventListener() {
            public void serialEvent(SerialPortEvent e) {
                //System.out.println("-->" + e.getEventType());
                if(e.getEventType() == SerialPortEvent.DATA_AVAILABLE) {
                    try {
                        //System.out.println(is.available());
                        int x = 0;
                        byte[] msgPack = new byte[35];
                        while(true) {
                            int j = is.read(msgPack, x, msgPack.length - x);
                            System.out.println("j=" + j);
                            if(j <= 0)
                                break;
                            x += j;
                            if(false)
                                break;
//                            System.out.println("x->" + x);
//                            for(int i = 0;i < 4;i++) {
//                                int newData;
//                                if((newData = is.read()) != -1) {
//                                    msgPack[i] = (byte) newData;
//                                    System.out.println(newData);
//                                } else {
//                                    break;
//                                }
//                                System.out.println("--------");
//                            }
                        }
                        System.out.println("x-> " + x);
                        for(byte a : msgPack) {
                            System.out.print(Integer.toHexString(a) + " ");
                        }
                        System.out.println();
                        System.out.println(new String(msgPack, 0, 34));
                        if(1 == 1)
                            return;
                    } catch(Exception es) {
                        es.printStackTrace();
                    }
                }
            }
        });
        sPort.notifyOnDataAvailable(true);
        sPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);

------解决方案--------------------

http://download.oracle.com/docs/cd/E17802_01/products/products/javacomm/reference/api/index.html

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