In addition to an id field, each java.awt.Event also contains a modifier field that provides additional information about the event. For example, you might want to know which key or which mouse button triggered an event. The Event class defines a handful of constants that provide such information. Table 8-6 lists the modifier constants. We'll show how to use these later in this chapter, but it's useful to have them handy for reference.
|Event Modifier Constant||Type||Meaning|
|ALT_MASK||Keyboard||ALT key is down.|
|ALT_MASK||Mouse Button||Button 2 is pressed.|
|CTRL_MASK||Keyboard||CONTROL key is down.|
|DOWN||Function Key||DOWN key is pressed.|
|END||Function Key||END key is pressed.|
|F1 - F12||Function Key||FUNCTION ...|