twowayserialcomm.java

双向传输协议

package Testing;
import gnu.io.CommPort;
import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;


import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;

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(9600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
               // the default is 57600 I change to 9600
                
                InputStream in = serialPort.getInputStream();
                OutputStream out = serialPort.getOutputStream();
                
                (new Thread(new SerialReader(in))).start();
                (new Thread(new SerialWriter(out))).start();

            }
            else
            {
                System.out.println("Error: Only serial ports are handled by this example.");
            }
        }     
    }
    
    /** */
    public static class SerialReader implements Runnable 
    {
        InputStream in;
        
        public SerialReader ( InputStream in )
        {
            this.in = in;
        }
        
        public void run ()
        {
            byte[] buffer = new byte[1024];
            int len = -1;
            try
            {
                while ( ( len = this.in.read(buffer)) > -1 )
                {
                    System.out.print(new String(buffer,0,len));
                }
            }
            catch ( IOException e )
            {
                e.printStackTrace();
            }            
        }
    }

    /** */
    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();
            }            
        }
    }
    
    
   
	static void listPorts()
    {
        Enumeration portEnum = CommPortIdentifier.getPortIdentifiers();
        while ( portEnum.hasMoreElements() ) 
        {
            CommPortIdentifier portIdentifier = (CommPortIdentifier) portEnum.nextElement();
            System.out.println(portIdentifier.getName()  +  " - " +  getPortTypeName(portIdentifier.getPortType()) );
        }        
    }
    
    static String getPortTypeName ( int portType )
    {
        switch ( portType )
        {
            case CommPortIdentifier.PORT_I2C:
                return "I2C";
            case CommPortIdentifier.PORT_PARALLEL:
                return "Parallel";
            case CommPortIdentifier.PORT_RAW:
                return "Raw";
            case CommPortIdentifier.PORT_RS485:
                return "RS485";
            case CommPortIdentifier.PORT_SERIAL:
                return "Serial";
            default:
                return "unknown type";
        }
    }

    
    public static void main ( String[] args )
    {
        try
        {
            (new TwoWaySerialComm()).connect("COM1");
        }
        catch ( Exception e )
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}