SWING - Event Classes


Advertisements


Event classes represent the event. Java provides various Event classes, however, only those which are more frequently used will be discussed.

EventObject Class

It is the root class from which all event state objects shall be derived. All Events are constructed with a reference to the object, the source, that is logically deemed to be the object upon which the Event in question initially occurred upon. This class is defined in java.util package.

Class Declaration

Following is the declaration for java.util.EventObject class −

public class EventObject
   extends Object
      implements Serializable

Field

Following are the fields for java.util.EventObject class −

protected Object source − The object on which the Event initially occurred.

Class Constructors

Sr.No. Constructor & Description
1

EventObject(Object source)

Constructs a prototypical Event.

Class Methods

Sr.No. Method & Description
1

Object getSource()

The object on which the Event initially occurred.

2

String toString()

Returns a String representation of this EventObject.

Methods Inherited

This class inherits methods from the following class −

  • java.lang.Object

SWING Event Classes

Following is the list of commonly used Event classes.

Sr.No. Class & Description
1 AWTEvent

It is the root event class for all SWING events. This class and its subclasses supercede the original java.awt.Event class.

2 ActionEvent

The ActionEvent is generated when the button is clicked or the item of a list is double-clicked.

3 InputEvent

The InputEvent class is the root event class for all component-level input events.

4 KeyEvent

On entering the character the Key event is generated.

5 MouseEvent

This event indicates a mouse action occurred in a component.

6 WindowEvent

The object of this class represents the change in the state of a window.

7 AdjustmentEvent

The object of this class represents the adjustment event emitted by Adjustable objects.

8 ComponentEvent

The object of this class represents the change in the state of a window.

9 ContainerEvent

The object of this class represents the change in the state of a window.

10 MouseMotionEvent

The object of this class represents the change in the state of a window.

11 PaintEvent

The object of this class represents the change in the state of a window.



Advertisements