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Class java.awt.event.ActionEvent 

java.lang.Object
    |
    +----java.util.EventObject
            |
            +----java.awt.AWTEvent
                    |
                    +----java.awt.event.ActionEvent
public class ActionEvent
extends AWTEvent
A semantic event which indicates that a component-defined action occured. This high-level event is generated by a component (such as a Button) when the component-specific action occurs (such as being pressed). The event is passed to every every ActionListener object that registered to receive such events using the component's addActionListener method.

The object that implements the ActionListener interface gets this ActionEvent when the event occurs. The listener is therefore spared the details of processing individual mouse movements and mouse clicks, and can instead process a "meaningful" (semantic) event like "button pressed".

See Also:
ActionListener, Tutorial: Java 1.1 Event Model, Reference: The Java Class Libraries (update file)

Variable Index

o ACTION_FIRST
The first number in the range of ids used for action events.
o ACTION_LAST
The last number in the range of ids used for action events.
o ACTION_PERFORMED
This event id indicates that a meaningful action occured.
o ALT_MASK
The alt modifier.
o CTRL_MASK
The control modifier.
o META_MASK
The meta modifier.
o SHIFT_MASK
The shift modifier.

Constructor Index

o ActionEvent(Object, int, String)
Constructs an ActionEvent object.
o ActionEvent(Object, int, String, int)
Constructs an ActionEvent object with modifier keys.

Method Index

o getActionCommand()
Returns the command string associated with this action.
o getModifiers()
Returns the modifier keys held down during this action event.
o paramString()
Returns a parameter string identifying this action event.

Variables

o SHIFT_MASK 
public static final int SHIFT_MASK
The shift modifier. An indicator that the shift key was held down during the event.

o CTRL_MASK 
public static final int CTRL_MASK
The control modifier. An indicator that the control key was held down during the event.

o META_MASK 
public static final int META_MASK
The meta modifier. An indicator that the meta key was held down during the event.

o ALT_MASK 
public static final int ALT_MASK
The alt modifier. An indicator that the alt key was held down during the event.

o ACTION_FIRST 
public static final int ACTION_FIRST
The first number in the range of ids used for action events.

o ACTION_LAST 
public static final int ACTION_LAST
The last number in the range of ids used for action events.

o ACTION_PERFORMED 
public static final int ACTION_PERFORMED
This event id indicates that a meaningful action occured.

Constructors

o ActionEvent 
public ActionEvent(Object source,
                   int id,
                   String command)
Constructs an ActionEvent object.

Parameters:
source - the object that originated the event
id - an integer that identifies the event
command - a string that may specify a command (possibly one of several) associated with the event
o ActionEvent 
public ActionEvent(Object source,
                   int id,
                   String command,
                   int modifiers)
Constructs an ActionEvent object with modifier keys.

Parameters:
source - the object that originated the event
id - an integer that identifies the event
command - a string that may specify a command (possibly one of several) associated with the event
modifiers - the modifier keys held down during this action

Methods

o getActionCommand 
public String getActionCommand()
Returns the command string associated with this action. This string allows a "modal" component to specify one of several commands, depending on its state. For example, a single button might toggle between "show details" and "hide details". The source object and the event would be the same in each case, but the command string would identify the intended action.

Returns:
the string identifying the command for this event
o getModifiers 
public int getModifiers()
Returns the modifier keys held down during this action event.

Returns:
the integer sum of the modifier constants
o paramString 
public String paramString()
Returns a parameter string identifying this action event. This method is useful for event-logging and for debugging.

Returns:
a string identifying the event and its associated command
Overrides:
paramString in class AWTEvent
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