simplecomm.java

来自「源码为科学出版社出版的英文<java设计模式>(影印版)所用的所有例」· Java 代码 · 共 94 行

import java.awt.*;
import java.io.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
import java.util.*;
import javax.comm.*;

public class SimpleComm extends JxFrame  
   implements ListSelectionListener
{
     CommPortIdentifier portId;
     Enumeration portEnum;
     Vector ports;

     JawtList status;
     JList portList;
     JScrollPane psw;
     int lastIndex;
        
  public SimpleComm() {
     
     super ("Comm Singleton");
     JPanel jp = new JPanel();
     getContentPane().add(jp);
     jp.setLayout (new BorderLayout());
     
     ports = new Vector();
     portList = new JList(ports);
     psw = new JScrollPane();
     psw.setBorder(new BevelBorder(BevelBorder.LOWERED));
     psw.getViewport().setView (portList);
     jp.add("West", psw);
     portList.addListSelectionListener (this);
     lastIndex = -1;       //index of last selected com port

     //now add status list on right
     status =  new JawtList(20);
     jp.add("Center", status);

     loadPorts();    //load into list box
     setSize(new Dimension(300,200));
     setVisible(true);


  }
 //------------------------------------
  public void valueChanged(ListSelectionEvent ls) {
     
     int index = portList.getSelectedIndex();
     if(index != lastIndex) {
      lastIndex = index;      //debounces mouse unclick
      //get port name back from list box
      String portName = (String)ports.elementAt (index);
      try {
         //try to get port ownership
         portId = CommPortIdentifier.getPortIdentifier(portName);
         
         //if successful, open the port
         CommPort cp = portId.open("SimpleComm",100);
         //report success
         status.add("Port opened: "+portName);
      }
      catch(NoSuchPortException e){
        status.add("No such port: "+portName);
      }
       catch(PortInUseException e){
           status.add (portName+" in use by: "+portId.getCurrentOwner());
       }
     }
  }
 //------------------------------------
  private void loadPorts() {
     portEnum = CommPortIdentifier.getPortIdentifiers();

        while (portEnum.hasMoreElements()) {
            portId = (CommPortIdentifier) portEnum.nextElement();
            if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) 
               {
               ports.addElement (portId.getName());
               }
        }
        //add bogus port
        ports.addElement("COM5");
        psw.doLayout ();
        psw.validate();
  }
  //------------------------------------
  public static void main(String[] args) {
         new SimpleComm();
    }

}