java使用的端口是什么？ [关闭]

Question

我写了这段 java J2SE 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;
public class TwoWaySerialComm 
{
    public TwoWaySerialComm()
    {
        super();
    }
    void connect ( String portName ) throws Exception
    {
        CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
        if ( portIdentifier.isCurrentlyOwned() )
        {
            System.out.println("Error: Port is currently in use");
        }
        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);

                InputStream in = serialPort.getInputStream();
                OutputStream out = serialPort.getOutputStream();

                (new Thread(new SerialWriter(out))).start();

                serialPort.addEventListener(new SerialReader(in));
                serialPort.notifyOnDataAvailable(true);

            }
            else
            {
                System.out.println("Error: Only serial ports are handled by this example.");
            }
        }     
    }
    public static class SerialReader implements SerialPortEventListener 
    {
        private InputStream in;
        private byte[] buffer = new byte[1024];

        public SerialReader ( InputStream in )
        {
            this.in = in;
        }

        public void serialEvent(SerialPortEvent arg0) {
            int data;

            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));
            }
            catch ( IOException e )
            {
                e.printStackTrace();
                System.exit(-1);
            }             
        }
    }
    public static class SerialWriter implements Runnable 
    {
        OutputStream out;

        public SerialWriter ( OutputStream out )
        {
            this.out = out;
        }

        public void run ()
        {
            try
            {                
                int c = 0;
                while ( ( c = System.in.read()) > -1 )
                {
                    this.out.write(c);
                }                
            }
            catch ( IOException e )
            {
                e.printStackTrace();
                System.exit(-1);
            }            
        }
    }
    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        try
        {
            (new TwoWaySerialComm()).connect("COM4");
        }
        catch ( Exception e )
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

我创建了一个与系统同时启动的批处理文件：

java TwoWaySerialComm

在control panel 的scheduled tasks 中，我创建了一个任务以在每次系统启动时启动批处理文件。

那么在这种情况下这个java程序使用的socketport是什么？

Answer 1

您的示例使用 JavaComm API（gnu.io 命名空间）来访问串行端口（在您的示例中，您正在访问 COM4）。

这与 TCP/IP 套接字 API 无关。您的示例中没有涉及 TCP/IP 网络。