Java 键盘事件处理 KeyEvent

import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;

public class sampletest
{
public static void main(String[] args)
{
myKeyEvent samp=new myKeyEvent();
}
}

class myKeyEvent extends JFrame
{
public myKeyEvent()
{
super();
final JLabel label=new JLabel();
label.setText("备注：");
this.getContentPane().add(label);

final JScrollPane scrollPane=new JScrollPane();
this.getContentPane().add(scrollPane);

JTextArea textArea=new JTextArea();
textArea.addKeyListener(new aKeyListener());
textArea.setLineWrap(true);
textArea.setRows(3);
textArea.setColumns(15);
scrollPane.setViewportView(textArea);
this.setVisible(true);
this.setBounds(39,39,400,400);
}

class aKeyListener implements KeyListener
{
public void keyPressed(KeyEvent e)
{
String keyText=KeyEvent.getKeyText(e.getKeyCode());
if(e.isActionKey())
{
System.out.println("您按下的是动作键”"+keyText+"“");
}
else
{
System.out.println("您按下的是非动作键“"+keyText+"“");
char keyChar=e.getKeyChar();
switch(keyChar)
{
case KeyEvent.VK_CONTROL:
System.out.println("Ctrl键被按下");
break;
case KeyEvent.VK_ALT:
System.out.println("Alt键被按下");
break;
case KeyEvent.VK_SHIFT:
System.out.println("Shift键被按下");
break;
}
}
}

public void keyTyped(KeyEvent e)
{
System.out.println("此次输入的是“"+e.getKeyChar()+"”");
}

public void keyReleased(KeyEvent e)
{
String keyText=KeyEvent.getKeyText(e.getKeyCode());
System.out.println("您释放的是“"+keyText+"”键");
System.out.println();
}
}
}