java.awt
Class Event

java.lang.Object
  |
  +--java.awt.Event

public class Event

extends Object

Event is a platform-independent class that encapsulates events from the local Graphical User Interface(GUI) platform.

The event contains an id which indicates the type of event it is and which other Event variables are relavent for the event. For keyboard events, key will contain a value indicating the key that was activated and modifiers will contain the modifiers. For KEY_PRESS and KEY_RELEASE event ids, the value of key will be the unicode character code for the key; for KEY_ACTION and KEY_ACTION_RELEASE, the value of key will be one of the defined action-key identifiers in the Event class (PGUP, PGDN, F1, F2, etc).

Field Summary

static int	ACTION_EVENT An action event.
static int	ALT_MASK The alt modifier constant.
Object	arg An arbitrary argument.
int	clickCount The number of consecutive clicks.
static int	CTRL_MASK The control modifier constant.
static int	DOWN The down arrow action-key.
static int	END The end action-key.
Event	evt The next event.
static int	F1 The F1 function action-key.
static int	F10 The F10 function action-key.
static int	F11 The F11 function action-key.
static int	F12 The F12 function action-key.
static int	F2 The F2 function action-key.
static int	F3 The F3 function action-key.
static int	F4 The F4 function action-key.
static int	F5 The F5 function action-key.
static int	F6 The F6 function action-key.
static int	F7 The F7 function action-key.
static int	F8 The F8 function action-key.
static int	F9 The F9 function action-key.
static int	GOT_FOCUS A component gained the focus.
static int	HOME The home action-key.
int	id The type of this event.
int	key The key that was pressed in a keyboard event.
static int	KEY_ACTION The action-key press keyboard event.
static int	KEY_ACTION_RELEASE The action-key release keyboard event.
static int	KEY_PRESS The key press keyboard event.
static int	KEY_RELEASE The key release keyboard event.
static int	LEFT The left arrow action-key.
static int	LIST_DESELECT
static int	LIST_SELECT
static int	LOAD_FILE A file loading event.
static int	LOST_FOCUS A component lost the focus.
static int	META_MASK The meta modifier constant.
int	modifiers The state of the modifier keys.
static int	MOUSE_DOWN The mouse down event.
static int	MOUSE_DRAG The mouse drag event.
static int	MOUSE_ENTER The mouse enter event.
static int	MOUSE_EXIT The mouse exit event.
static int	MOUSE_MOVE The mouse move event.
static int	MOUSE_UP The mouse up event.
static int	PGDN The page down action-key.
static int	PGUP The page up action-key.
static int	RIGHT The right arrow action-key.
static int	SAVE_FILE A file saving event.
static int	SCROLL_ABSOLUTE The absolute scroll event.
static int	SCROLL_LINE_DOWN The line down scroll event.
static int	SCROLL_LINE_UP The line up scroll event.
static int	SCROLL_PAGE_DOWN The page down scroll event.
static int	SCROLL_PAGE_UP The page up scroll event.
static int	SHIFT_MASK The shift modifier constant.
Object	target The target component.
static int	UP The up arrow action-key.
long	when The time stamp.
static int	WINDOW_DEICONIFY The de-iconify window event.
static int	WINDOW_DESTROY The destroy window event.
static int	WINDOW_EXPOSE The expose window event.
static int	WINDOW_ICONIFY The iconify window event.
static int	WINDOW_MOVED The move window event.
int	x The x coordinate of the event.
int	y The y coordinate of the event.

Constructor Summary

Event(Object target, int id, Object arg)
Constructs an event with the specified target component, event type, and argument.

Event(Object target, long when, int id, int x, int y, int key, int modifiers)
Constructs an event with the specified target component, time stamp, event type, x and y coordinates, keyboard key, state of the modifier keys and an argument set to null.

Event(Object target, long when, int id, int x, int y, int key, int modifiers, Object arg)
Constructs an event with the specified target component, time stamp, event type, x and y coordinates, keyboard key, state of the modifier keys and argument.

Method Summary

boolean	controlDown() Checks if the control key is down.
boolean	metaDown() Checks if the meta key is down.
protected String	paramString() Returns the parameter String of this Event.
boolean	shiftDown() Checks if the shift key is down.
String	toString() Returns the String representation of this Event's values.
void	translate(int x, int y) Translates an event relative to the given component.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

SHIFT_MASK

public static final int SHIFT_MASK

The shift modifier constant.

See Also:

Constant Field Values

CTRL_MASK

public static final int CTRL_MASK

The control modifier constant.

See Also:

Constant Field Values

META_MASK

public static final int META_MASK

The meta modifier constant.

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Constant Field Values

ALT_MASK

public static final int ALT_MASK

The alt modifier constant.

See Also:

Constant Field Values

HOME

public static final int HOME

The home action-key.

See Also:

Constant Field Values

END

public static final int END

The end action-key.

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Constant Field Values

PGUP

public static final int PGUP

The page up action-key.

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Constant Field Values

PGDN

public static final int PGDN

The page down action-key.

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Constant Field Values

UP

public static final int UP

The up arrow action-key.

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Constant Field Values

DOWN

public static final int DOWN

The down arrow action-key.

See Also:

Constant Field Values

LEFT

public static final int LEFT

The left arrow action-key.

See Also:

Constant Field Values

RIGHT

public static final int RIGHT

The right arrow action-key.

See Also:

Constant Field Values

F1

public static final int F1

The F1 function action-key.

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Constant Field Values

F2

public static final int F2

The F2 function action-key.

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Constant Field Values

F3

public static final int F3

The F3 function action-key.

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Constant Field Values

F4

public static final int F4

The F4 function action-key.

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Constant Field Values

F5

public static final int F5

The F5 function action-key.

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Constant Field Values

F6

public static final int F6

The F6 function action-key.

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Constant Field Values

F7

public static final int F7

The F7 function action-key.

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Constant Field Values

F8

public static final int F8

The F8 function action-key.

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Constant Field Values

F9

public static final int F9

The F9 function action-key.

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Constant Field Values

F10

public static final int F10

The F10 function action-key.

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Constant Field Values

F11

public static final int F11

The F11 function action-key.

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Constant Field Values

F12

public static final int F12

The F12 function action-key.

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Constant Field Values

WINDOW_DESTROY

public static final int WINDOW_DESTROY

The destroy window event.

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Constant Field Values

WINDOW_EXPOSE

public static final int WINDOW_EXPOSE

The expose window event.

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Constant Field Values

WINDOW_ICONIFY

public static final int WINDOW_ICONIFY

The iconify window event.

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Constant Field Values

WINDOW_DEICONIFY

public static final int WINDOW_DEICONIFY

The de-iconify window event.

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Constant Field Values

WINDOW_MOVED

public static final int WINDOW_MOVED

The move window event.

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Constant Field Values

KEY_PRESS

public static final int KEY_PRESS

The key press keyboard event.

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Constant Field Values

KEY_RELEASE

public static final int KEY_RELEASE

The key release keyboard event.

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Constant Field Values

KEY_ACTION

public static final int KEY_ACTION

The action-key press keyboard event.

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Constant Field Values

KEY_ACTION_RELEASE

public static final int KEY_ACTION_RELEASE

The action-key release keyboard event.

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Constant Field Values

MOUSE_DOWN

public static final int MOUSE_DOWN

The mouse down event.

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Constant Field Values

MOUSE_UP

public static final int MOUSE_UP

The mouse up event.

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Constant Field Values

MOUSE_MOVE

public static final int MOUSE_MOVE

The mouse move event.

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Constant Field Values

MOUSE_ENTER

public static final int MOUSE_ENTER

The mouse enter event.

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Constant Field Values

MOUSE_EXIT

public static final int MOUSE_EXIT

The mouse exit event.

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Constant Field Values

MOUSE_DRAG

public static final int MOUSE_DRAG

The mouse drag event.

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Constant Field Values

SCROLL_LINE_UP

public static final int SCROLL_LINE_UP

The line up scroll event.

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Constant Field Values

SCROLL_LINE_DOWN

public static final int SCROLL_LINE_DOWN

The line down scroll event.

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Constant Field Values

SCROLL_PAGE_UP

public static final int SCROLL_PAGE_UP

The page up scroll event.

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Constant Field Values

SCROLL_PAGE_DOWN

public static final int SCROLL_PAGE_DOWN

The page down scroll event.

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Constant Field Values

SCROLL_ABSOLUTE

public static final int SCROLL_ABSOLUTE

The absolute scroll event.

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Constant Field Values

LIST_SELECT

public static final int LIST_SELECT

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Constant Field Values

LIST_DESELECT

public static final int LIST_DESELECT

See Also:

Constant Field Values

ACTION_EVENT

public static final int ACTION_EVENT

An action event.

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Constant Field Values

LOAD_FILE

public static final int LOAD_FILE

A file loading event.

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Constant Field Values

SAVE_FILE

public static final int SAVE_FILE

A file saving event.

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Constant Field Values

GOT_FOCUS

public static final int GOT_FOCUS

A component gained the focus.

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Constant Field Values

LOST_FOCUS

public static final int LOST_FOCUS

A component lost the focus.

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Constant Field Values

target

public Object target

The target component.

when

public long when

The time stamp.

id

public int id

The type of this event.

x

public int x

The x coordinate of the event.

y

public int y

The y coordinate of the event.

key

public int key

The key that was pressed in a keyboard event.

modifiers

public int modifiers

The state of the modifier keys.

clickCount

public int clickCount

The number of consecutive clicks. This field is relevant only for MOUSE_DOWN events. If the field isn't set it will be 0. Otherwise, it will be 1 for single-clicks, 2 for double-clicks, and so on.

arg

public Object arg

An arbitrary argument.

evt

public Event evt

The next event. Used when putting events into a linked list.

Constructor Detail

Event

public Event(Object target,
             long when,
             int id,
             int x,
             int y,
             int key,
             int modifiers,
             Object arg)

Constructs an event with the specified target component, time stamp, event type, x and y coordinates, keyboard key, state of the modifier keys and argument.

Parameters:

target - the target component

when - the time stamp

id - the event type

x - the x coordinate

y - the y coordinate

key - the key pressed in a keyboard event

modifiers - the state of the modifier keys

arg - the specified argument

Event

public Event(Object target,
             long when,
             int id,
             int x,
             int y,
             int key,
             int modifiers)

Constructs an event with the specified target component, time stamp, event type, x and y coordinates, keyboard key, state of the modifier keys and an argument set to null.

Parameters:

target - the target component

when - the time stamp

id - the event type

x - the x coordinate

y - the y coordinate

key - the key pressed in a keyboard event

modifiers - the state of the modifier keys

Event

public Event(Object target,
             int id,
             Object arg)

Constructs an event with the specified target component, event type, and argument.

Parameters:

target - the target component

id - the event type

arg - the specified argument

Method Detail

translate

public void translate(int x,
                      int y)

Translates an event relative to the given component. This involves at a minimum translating the coordinates so they make sense within the given component. It may also involve translating a region in the case of an expose event.

Parameters:

x - the x coordinate

y - the y coordinate

shiftDown

public boolean shiftDown()

Checks if the shift key is down.

See Also:

modifiers, controlDown(), metaDown()

controlDown

public boolean controlDown()

Checks if the control key is down.

See Also:

modifiers, shiftDown(), metaDown()

metaDown

public boolean metaDown()

Checks if the meta key is down.

See Also:

modifiers, shiftDown(), controlDown()

paramString

protected String paramString()

Returns the parameter String of this Event.

toString

public String toString()

Returns the String representation of this Event's values.

Overrides:

toString in class Object