请教键盘响应事件?

我写一个键盘响应,但没反映呀 ? 哪位好心帮帮我.
KeyListener c = new KeyListener()
{
public void keyPressed(KeyEvent e)
{
switch(e.getKeyCode()){
case 0x25: sendCommand("up");break;
case 0x26:
}
public void keyReleased(KeyEvent e)
{
}
public void keyTyped(KeyEvent e)
{
}
};