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# Class java.awt.Event

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

public class Event
extends Object
implements Serializable

`Event` is a platform-independent class that encapsulates events from the platform's Graphical User Interface in the Java 1.0 event model. In Java 1.1 and later versions, the `Event` class is maintained only for backwards compatibilty. The information in this class description is provided to assist programmers in converting Java 1.0 programs to the new event model.

In the Java 1.0 event model, an event contains an `id` field that indicates what type of event it is and which other `Event` variables are relevant for the event.

For keyboard events, `key` contains a value indicating which key was activated, and `modifiers` contains the modifiers for that event. For the KEY_PRESS and KEY_RELEASE event ids, the value of `key` is the unicode character code for the key. For KEY_ACTION and KEY_ACTION_RELEASE, the value of `key` is one of the defined action-key identifiers in the `Event` class (`PGUP`, `PGDN`, `F1`, `F2`, etc).

##

ACTION_EVENT
  This event indicates that the user wants some action to occur.
ALT_MASK
  This flag indicates that the Alt key was down when the event occurred.
arg
  An arbitrary argument of the event.
BACK_SPACE
  The BackSpace key.
CAPS_LOCK
  The Caps Lock key, a non-ASCII action key.
clickCount
  For `MOUSE_DOWN` events, this field indicates the number of consecutive clicks.
CTRL_MASK
  This flag indicates that the Control key was down when the event occurred.
DELETE
  The Delete key.
DOWN
  The Down Arrow key, a non-ASCII action key.
END
  The End key, a non-ASCII action key.
ENTER
  The Enter key.
ESCAPE
  The Escape key.
evt
  The next event.
F1
  The F1 function key, a non-ASCII action key.
F10
  The F10 function key, a non-ASCII action key.
F11
  The F11 function key, a non-ASCII action key.
F12
  The F12 function key, a non-ASCII action key.
F2
  The F2 function key, a non-ASCII action key.
F3
  The F3 function key, a non-ASCII action key.
F4
  The F4 function key, a non-ASCII action key.
F5
  The F5 function key, a non-ASCII action key.
F6
  The F6 function key, a non-ASCII action key.
F7
  The F7 function key, a non-ASCII action key.
F8
  The F8 function key, a non-ASCII action key.
F9
  The F9 function key, a non-ASCII action key.
GOT_FOCUS
  A component gained the focus.
HOME
  The Home key, a non-ASCII action key.
id
  Indicates which type of event the event is, and which other `Event` variables are relevant for the event.
INSERT
  The Insert key, a non-ASCII action key.
key
  The key code of the key that was pressed in a keyboard event.
KEY_ACTION
  The user has pressed a non-ASCII action key.
KEY_ACTION_RELEASE
  The user has released a non-ASCII action key.
KEY_PRESS
  The user has pressed a normal key.
KEY_RELEASE
  The user has released a normal key.
LEFT
  The Left Arrow key, a non-ASCII action key.
LIST_DESELECT
  An item in a list has been deselected.
LIST_SELECT
  An item in a list has been selected.
LOAD_FILE
  A file loading event.
LOST_FOCUS
  A component lost the focus.
META_MASK
  This flag indicates that the Meta key was down when the event occurred.
modifiers
  The state of the modifier keys.
MOUSE_DOWN
  The user has pressed the mouse button.
MOUSE_DRAG
  The user has moved the mouse with a button pressed.
MOUSE_ENTER
  The mouse has entered a component.
MOUSE_EXIT
  The mouse has exited a component.
MOUSE_MOVE
  The mouse has moved with no button pressed.
MOUSE_UP
  The user has released the mouse button.
NUM_LOCK
  The Num Lock key, a non-ASCII action key.
PAUSE
  The Pause key, a non-ASCII action key.
PGDN
  The Page Down key, a non-ASCII action key.
PGUP
  The Page Up key, a non-ASCII action key.
PRINT_SCREEN
  The Print Screen key, a non-ASCII action key.
RIGHT
  The Right Arrow key, a non-ASCII action key.
SAVE_FILE
  A file saving event.
SCROLL_ABSOLUTE
  The user has moved the bubble (thumb) in a scroll bar, moving to an "absolute" position, rather than to an offset from the last postion.
SCROLL_BEGIN
  The scroll begin event.
SCROLL_END
  The scroll end event.
SCROLL_LINE_DOWN
  The user has activated the line down area of a scroll bar.
SCROLL_LINE_UP
  The user has activated the line up area of a scroll bar.
SCROLL_LOCK
  The Scroll Lock key, a non-ASCII action key.
SCROLL_PAGE_DOWN
  The user has activated the page down area of a scroll bar.
SCROLL_PAGE_UP
  The user has activated the page up area of a scroll bar.
SHIFT_MASK
  This flag indicates that the Shift key was down when the event occurred.
TAB
  The Tab key.
target
  The target component.
UP
  The Up Arrow key, a non-ASCII action key.
when
  The time stamp.
WINDOW_DEICONIFY
  The user has asked the window manager to de-iconify the window.
WINDOW_DESTROY
  The user has asked the window manager to kill the window.
WINDOW_EXPOSE
  The user has asked the window manager to expose the window.
WINDOW_ICONIFY
  The user has asked the window manager to iconify the window.
WINDOW_MOVED
  The user has asked the window manager to move the window.
x
  The x coordinate of the event.
y
  The y coordinate of the event.

##

Event(Object, int, Object)
  Creates an instance of `Event` with the specified target component, event type, and argument.
Event(Object, long, int, int, int, int, int)
  Creates an instance of `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, long, int, int, int, int, int, Object)
  Creates an instance of `Event` with the specified target component, time stamp, event type, x and y coordinates, keyboard key, state of the modifier keys, and argument.

##

controlDown()
  Checks if the Control key is down.
metaDown()
  Checks if the Meta key is down.
paramString()
  Returns the parameter string representing this event.
shiftDown()
  Checks if the Shift key is down.
toString()
  Returns a representation of this event's values as a string.
translate(int, int)
  Translates this event so that its x and y coordinates are increased by dx and dy, respectively.

##

SHIFT_MASK

     public static final int SHIFT_MASK

  This flag indicates that the Shift key was down when the event occurred.

CTRL_MASK

     public static final int CTRL_MASK

  This flag indicates that the Control key was down when the event occurred.

META_MASK

     public static final int META_MASK

  This flag indicates that the Meta key was down when the event occurred. For mouse events, this flag indicates that the right button was pressed or released.

ALT_MASK

     public static final int ALT_MASK

  This flag indicates that the Alt key was down when the event occurred. For mouse events, this flag indicates that the middle mouse button was pressed or released.

HOME

     public static final int HOME

  The Home key, a non-ASCII action key.

END

     public static final int END

  The End key, a non-ASCII action key.

PGUP

     public static final int PGUP

  The Page Up key, a non-ASCII action key.

PGDN

     public static final int PGDN

  The Page Down key, a non-ASCII action key.

UP

     public static final int UP

  The Up Arrow key, a non-ASCII action key.

DOWN

     public static final int DOWN

  The Down Arrow key, a non-ASCII action key.

LEFT

     public static final int LEFT

  The Left Arrow key, a non-ASCII action key.

RIGHT

     public static final int RIGHT

  The Right Arrow key, a non-ASCII action key.

F1

     public static final int F1

  The F1 function key, a non-ASCII action key.

F2

     public static final int F2

  The F2 function key, a non-ASCII action key.

F3

     public static final int F3

  The F3 function key, a non-ASCII action key.

F4

     public static final int F4

  The F4 function key, a non-ASCII action key.

F5

     public static final int F5

  The F5 function key, a non-ASCII action key.

F6

     public static final int F6

  The F6 function key, a non-ASCII action key.

F7

     public static final int F7

  The F7 function key, a non-ASCII action key.

F8

     public static final int F8

  The F8 function key, a non-ASCII action key.

F9

     public static final int F9

  The F9 function key, a non-ASCII action key.

F10

     public static final int F10

  The F10 function key, a non-ASCII action key.

F11

     public static final int F11

  The F11 function key, a non-ASCII action key.

F12

     public static final int F12

  The F12 function key, a non-ASCII action key.

PRINT_SCREEN

     public static final int PRINT_SCREEN

  The Print Screen key, a non-ASCII action key.

SCROLL_LOCK

     public static final int SCROLL_LOCK

  The Scroll Lock key, a non-ASCII action key.

CAPS_LOCK

     public static final int CAPS_LOCK

  The Caps Lock key, a non-ASCII action key.

NUM_LOCK

     public static final int NUM_LOCK

  The Num Lock key, a non-ASCII action key.

PAUSE

     public static final int PAUSE

  The Pause key, a non-ASCII action key.

INSERT

     public static final int INSERT

  The Insert key, a non-ASCII action key.

ENTER

     public static final int ENTER

  The Enter key.

BACK_SPACE

     public static final int BACK_SPACE

  The BackSpace key.

TAB

     public static final int TAB

  The Tab key.

ESCAPE

     public static final int ESCAPE

  The Escape key.

DELETE

     public static final int DELETE

  The Delete key.

WINDOW_DESTROY

     public static final int WINDOW_DESTROY

  The user has asked the window manager to kill the window.

WINDOW_EXPOSE

     public static final int WINDOW_EXPOSE

  The user has asked the window manager to expose the window.

WINDOW_ICONIFY

     public static final int WINDOW_ICONIFY

  The user has asked the window manager to iconify the window.

WINDOW_DEICONIFY

     public static final int WINDOW_DEICONIFY

  The user has asked the window manager to de-iconify the window.

WINDOW_MOVED

     public static final int WINDOW_MOVED

  The user has asked the window manager to move the window.

KEY_PRESS

     public static final int KEY_PRESS

  The user has pressed a normal key.

KEY_RELEASE

     public static final int KEY_RELEASE

  The user has released a normal key.

KEY_ACTION

     public static final int KEY_ACTION

  The user has pressed a non-ASCII action key. The `key` field contains a value that indicates that the event occurred on one of the action keys, which comprise the 12 function keys, the arrow (cursor) keys, Page Up, Page Down, Home, End, Print Screen, Scroll Lock, Caps Lock, Num Lock, Pause, and Insert.

KEY_ACTION_RELEASE

     public static final int KEY_ACTION_RELEASE

  The user has released a non-ASCII action key. The `key` field contains a value that indicates that the event occurred on one of the action keys, which comprise the 12 function keys, the arrow (cursor) keys, Page Up, Page Down, Home, End, Print Screen, Scroll Lock, Caps Lock, Num Lock, Pause, and Insert.

MOUSE_DOWN

     public static final int MOUSE_DOWN

  The user has pressed the mouse button. The `ALT_MASK` flag indicates that the middle button has been pressed. The `META_MASK`flag indicates that the right button has been pressed.

  See Also:
    ALT_MASK, META_MASK

MOUSE_UP

     public static final int MOUSE_UP

  The user has released the mouse button. The `ALT_MASK` flag indicates that the middle button has been released. The `META_MASK`flag indicates that the right button has been released.

  See Also:
    ALT_MASK, META_MASK

MOUSE_MOVE

     public static final int MOUSE_MOVE

  The mouse has moved with no button pressed.

MOUSE_ENTER

     public static final int MOUSE_ENTER

  The mouse has entered a component.

MOUSE_EXIT

     public static final int MOUSE_EXIT

  The mouse has exited a component.

MOUSE_DRAG

     public static final int MOUSE_DRAG

  The user has moved the mouse with a button pressed. The `ALT_MASK` flag indicates that the middle button is being pressed. The `META_MASK` flag indicates that the right button is being pressed.

  See Also:
    ALT_MASK, META_MASK

SCROLL_LINE_UP

     public static final int SCROLL_LINE_UP

  The user has activated the line up area of a scroll bar.

SCROLL_LINE_DOWN

     public static final int SCROLL_LINE_DOWN

  The user has activated the line down area of a scroll bar.

SCROLL_PAGE_UP

     public static final int SCROLL_PAGE_UP

  The user has activated the page up area of a scroll bar.

SCROLL_PAGE_DOWN

     public static final int SCROLL_PAGE_DOWN

  The user has activated the page down area of a scroll bar.

SCROLL_ABSOLUTE

     public static final int SCROLL_ABSOLUTE

  The user has moved the bubble (thumb) in a scroll bar, moving to an "absolute" position, rather than to an offset from the last postion.

SCROLL_BEGIN

     public static final int SCROLL_BEGIN

  The scroll begin event.

SCROLL_END

     public static final int SCROLL_END

  The scroll end event.

LIST_SELECT

     public static final int LIST_SELECT

  An item in a list has been selected.

LIST_DESELECT

     public static final int LIST_DESELECT

  An item in a list has been deselected.

ACTION_EVENT

     public static final int ACTION_EVENT

  This event indicates that the user wants some action to occur.

LOAD_FILE

     public static final int LOAD_FILE

  A file loading event.

SAVE_FILE

     public static final int SAVE_FILE

  A file saving event.

GOT_FOCUS

     public static final int GOT_FOCUS

  A component gained the focus.

LOST_FOCUS

     public static final int LOST_FOCUS

  A component lost the focus.

target

     public Object target

  The target component. This indicates the component over which the event occurred or with which the event is associated.

when

     public long when

  The time stamp.

id

     public int id

  Indicates which type of event the event is, and which other `Event` variables are relevant for the 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 code of the key that was pressed in a keyboard event.

modifiers

     public int modifiers

  The state of the modifier keys.

  NOTE: changing the modifier keys is not recommended, because many native implementations do not recognize modifier changes. This is especially true when the shift modifier is changed.

clickCount

     public int clickCount

  For `MOUSE_DOWN` events, this field indicates the number of consecutive clicks. For other events, its value is `0`.

arg

     public Object arg

  An arbitrary argument of the event. The value of this field depends on the type of event.

evt

     public Event evt

  The next event. This field is set when putting events into a linked list.

##

Event

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

  Creates an instance of `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)

  Creates an instance of `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)

  Creates an instance of `Event` with the specified target component, event type, and argument.

  Parameters:
    target - the target component.
    id - the event type.
    arg - the specified argument.

##

translate

     public void translate(int x,
                           int y)

  Translates this event so that its x and y coordinates are increased by dx and dy, respectively.

  This method translates an event relative to the given component. This involves, at a minimum, translating the coordinates into the local coordinate system of the given component. It may also involve translating a region in the case of an expose event.

  Parameters:
    dx - the distance to translate the x coordinate.
    dy - the distance to translate the y coordinate.

shiftDown

     public boolean shiftDown()

  Checks if the Shift key is down.

  Returns:
    `true` if the key is down; `false` otherwise.
  See Also:
    modifiers, controlDown, metaDown

controlDown

     public boolean controlDown()

  Checks if the Control key is down.

  Returns:
    `true` if the key is down; `false` otherwise.
  See Also:
    modifiers, shiftDown, metaDown

metaDown

     public boolean metaDown()

  Checks if the Meta key is down.

  Returns:
    `true` if the key is down; `false` otherwise.
  See Also:
    modifiers, shiftDown, controlDown

paramString

     protected String paramString()

  Returns the parameter string representing this event. This string is useful for debugging.

  Returns:
    the parameter string of this event.

toString

     public String toString()

  Returns a representation of this event's values as a string.

  Returns:
    a string that represents the event and the values of its member fields.
  Overrides:
    toString in class Object
  See Also:
    paramString

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