Here is the answer,
A GUI component handles its events by implementing the required event listener interface.It adds its own event listener in order to keep a track of all events associated with it.AWT has Java1.0 and Java1.1 of Event handling in different manners: In Java1.0:Event handling is based on inheritance.A program catches and processes GUI events by subclassing GUI components and override either action() or handleEvent() methods.There are two possibilities in this scenario:
a)Each component is subclassed to specifically handle its target events. The results in too many classes.
b)All events or a subset for an entire hierarchy for handling a particular container; results in container's overridden action() or handleEvent() method and complex conditional statement for events processing.