Package is used for defining interfaces and classed that is used for event handling in AWT and SWING.AWTEvent is a subclass of EventObject class and it is superclass for all AWT events.getSource() method returns the source and toString() method returns the string equivalent of the event.EventObject is the superclass for all events which means it is the root of the Java event class hierarchy.Some common Java interfaces and the events they listen for and handle : Java Interfaces Event They Listen ActionListener Listens for and handles button clicks KeyListener Listens for and handles key events MouseListener Listens for and handles mouse events MouseMotionListener Listens for and handles mouse drag and move events TextListener Listens for and handles text changing events ItemListener Listens for and handles CheckBox and Listbox events AdjustmentListener Listens for and handles scrolling events Runnable Listens for and handles Threads and Run WindowListener Listens for and handles window events FocusListener Listens for and handles focus events Event Classes.It must implement methods to receive and process these notifications.It must have been registered with one or more sources to receive notifications about specific types of events.Implementing an interface without adding its required abstract methods result in a syntax error. Listeners are Java interfacesand since we are covering advance topics you must have the knowledge of interfaces that when we implement an interface by a class we must implement all interface’s methods because all the methods in an interface are abstract.It is an object which is notified when an event occurs.A method getSource() is associated with all events which returns the object on which the event is initially occurred.
A source can generate one or more types of events.This happens when the internal state of the object changes in some way.A source is an object that generates an Event.Events are supported by number of packages including java.util, java.awt,.Some examples of the events are Java Button Pressed Event, entering a character via keyboard, selecting an item in a list, clicking the mouse etc.Basically they are associated with a component.It is an object which describes a change in a source.4 Which Event is Performed on the Button Click in Java? Java Button Click Event What is An Event ?.3 Which Method is Used to Handle Button Click Event?.
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