Java串口编程学习2-读串口

如果读串口出现乱码，则：

1.可能是波特率设置不对

2.可能是数据编码格式不对

import gnu.io.*;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.IOException;
import java.io.InputStream;
import java.util.Enumeration;
import java.util.TooManyListenersException;

/**
 * Created by gbr on 13-12-12.
 */

class R_Frame extends Frame implements Runnable, ActionListener, SerialPortEventListener{
    static CommPortIdentifier portId;
    static Enumeration portList;
    InputStream inputStream;

    SerialPort serialPort;
    Thread readThread;
    String str = "";
    TextField out_message = new TextField("上面文本框显示接收到的数据");
    TextArea in_message = new TextArea();
    Button btnOpen = new Button("Open Comm");
    R_Frame(){
        super("串口接收数据");
        setSize(200, 200);
        setVisible(true);
        btnOpen.addActionListener(this);
        add(out_message, "South");
        add(in_message, "Center");
        add(btnOpen, "North");
    }

    public void actionPerformed(ActionEvent event){
        portList = CommPortIdentifier.getPortIdentifiers();
        while (portList.hasMoreElements()){
            portId = (CommPortIdentifier)portList.nextElement();
            if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL){
                if (portId.getName().equals("COM8")){
                    try{
                        serialPort = (SerialPort)portId.open("ReadComm", 2000);
                        out_message.setText("已经打开串口COM8，正在接收数据...");
                    } catch (PortInUseException e) {
                        out_message.setText("端口已被占用！");
                        e.printStackTrace();
                    }
                    try{
                        serialPort.addEventListener(this);
                    }catch (TooManyListenersException e){
                        out_message.setText("监听异常！");
                        e.printStackTrace();
                    }
                    serialPort.notifyOnDataAvailable(true);
                }
            }
        }
        readThread = new Thread(this);
        readThread.start();
    }
    public void run(){
        try{
            Thread.sleep(20);
        }catch (InterruptedException e){
            e.printStackTrace();
        }
    }

    public void serialEvent(SerialPortEvent event){
        try{
            serialPort.setSerialPortParams(115200,
                    SerialPort.DATABITS_8,
                    SerialPort.STOPBITS_1,
                    SerialPort.PARITY_NONE);
        }catch (UnsupportedCommOperationException e){
            e.printStackTrace();
        }

        byte[] readBuffer = new byte[200];
        try{
            inputStream = serialPort.getInputStream();
        }catch (IOException e){
            e.printStackTrace();
        }

        try{
            while (inputStream.available() > 0){
                int numBytes = inputStream.read(readBuffer);
            }
            str = new String(readBuffer);
            in_message.append( str + "
" );
        }catch (IOException e){
            e.printStackTrace();
        }
    }
}

public class ReadComm {
    public static void main( String[] args ){
        R_Frame R_win = new R_Frame();
        R_win.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
                //super.windowClosing(e);
            }
        });
        R_win.pack();
    }
}