Event

Name

Description

The Event class represents events that happen within the Java environment in a platform independent way. Events typically represent user actions, like typing a key or clicking the mouse. Although this class has been updated for the 1.1 release, it is only used for the 1.0 event model. When using the 1.1 event model, all events are represented by subclasses of java.awt.AWTEvent.

Class Definition

public class java.awt.Event extends java.lang.Object implements java.io.Serializable {
 // Constants public static final int ACTION_EVENT;
public static final int ALT_MASK;
public static final int BACK_SPACE; public static final int CAPS_LOCK; public static final int CTRL_MASK;
public static final int DELETE; public static final int DOWN;
public static final int END;
public static final int ENTER; public static final int ESCAPE; public static final int F1;
public static final int F2;
public static final int F3;
public static final int F4;
public static final int F5;
public static final int F6;
public static final int F7;
public static final int F8;
public static final int F9;
public static final int F10;
public static final int F11;
public static final int F12;
public static final int GOT_FOCUS;
public static final int HOME;
public static final int INSERT; public static final int KEY_ACTION;
public static final int KEY_ACTION_RELEASE;
public static final int KEY_PRESS;
public static final int KEY_RELEASE;
public static final int LEFT;
public static final int LIST_DESELECT;
public static final int LIST_SELECT;
public static final int LOAD_FILE;
public static final int LOST_FOCUS;
public static final int META_MASK;
public static final int MOUSE_DOWN;
public static final int MOUSE_DRAG;
public static final int MOUSE_ENTER;
public static final int MOUSE_EXIT;
public static final int MOUSE_MOVE;
public static final int MOUSE_UP;
public static final int NUM_LOCK; public static final int PAUSE; public static final int PGDN;
public static final int PGUP;
public static final int PRINT_SCREEN; public static final int RIGHT;
public static final int SAVE_FILE;
public static final int SCROLL_ABSOLUTE;
public static final int SCROLL_BEGIN; public static final int SCROLL_END; public static final int SCROLL_LINE_DOWN;
public static final int SCROLL_LINE_UP;
public static final int SCROLL_LOCK; public static final int SCROLL_PAGE_DOWN;
public static final int SCROLL_PAGE_UP;
public static final int SHIFT_MASK;
public static final int TAB; public static final int UP;
public static final int WINDOW_DEICONIFY;
public static final int WINDOW_DESTROY;
public static final int WINDOW_EXPOSE;
public static final int WINDOW_ICONIFY;
public static final int WINDOW_MOVED; // Variables public Object arg;
public int clickCount;
public Event evt;
public int id;
public int key;
public int modifiers;
public Object target;
public long when;
public int x;
public int y; // Constructors public Event (Object target, int id, Object arg);
public Event (Object target, long when, int id, int x, int y, int key, int modifiers);
public Event (Object target, long when, int id, int x, int y, int key, int modifiers, Object arg); // Instance Methods public boolean controlDown();
public boolean metaDown();
public boolean shiftDown();
public String toString();
public void translate (int x, int y); // Protected Instance Methods protected String paramString();
}

Constants

ACTION_EVENT

public static final int ACTION_EVENT

ID constant for Action Event.

ALT_MASK

public static final int ALT_MASK

Mask for ALT key.

BACK_SPACE

public static final int BACK_SPACE

ID constant for Backspace.

CAPS_LOCK

public static final int CAPS_LOCK

ID constant for Caps Lock key.

CTRL_MASK

public static final int CTRL_MASK

Mask for Control key.

DELETE

public static final int DELETE

ID constant for Delete.

DOWN

public static final int DOWN

ID constant for the down arrow key.

END

public static final int END

ID constant for End key.

ENTER

public static final int ENTER

ID constant for Enter key.

ESCAPE

public static final int ESCAPE

ID constant for Escape key.

public static final int F1

ID constant for F1 key.

public static final int F2

ID constant for F2 key.

public static final int F3

ID constant for F3 key.

public static final int F4

ID constant for F4 key.

public static final int F5

ID constant for F5 key.

public static final int F6

ID constant for F6 key.

public static final int F7

ID constant for F7 key.

public static final int F8

ID constant for F8 key.

public static final int F9

ID constant for F9 key.

public static final int F10

ID constant for F10 key.

public static final int F11

ID constant for F11 key.

public static final int F12

ID constant for F12 key.

GOT_FOCUS

public static final int GOT_FOCUS

ID constant for getting input focus Event.

HOME

public static final int HOME

ID constant for Home key.

INSERT

public static final int INSERT

ID constant for Insert key.

KEY_ACTION

public static final int KEY_ACTION

ID constant for Special Key Down Event.

KEY_ACTION_RELEASE

public static final int KEY_ACTION_RELEASE

ID constant for Special Key Up Event.

KEY_PRESS

public static final int KEY_PRESS

ID constant for Key Down Event.

KEY_RELEASE

public static final int KEY_RELEASE

ID constant for Key Up Event.

LEFT

public static final int LEFT

ID constant for the left arrow key.

LIST_DESELECT

public static final int LIST_DESELECT

ID constant for List DeSelect Event.

LIST_SELECT

public static final int LIST_SELECT

ID constant for List Select Event.

LOAD_FILE

public static final int LOAD_FILE

ID constant for File Load Event.

LOST_FOCUS

public static final int LOST_FOCUS

ID constant for losing input focus Event.

META_MASK

public static final int META_MASK

Mask for ALT key.

MOUSE_DOWN

public static final int MOUSE_DOWN

ID constant for Mouse Down Event.

MOUSE_DRAG

public static final int MOUSE_DRAG

ID constant for Mouse Drag Event.

MOUSE_ENTER

public static final int MOUSE_ENTER

ID constant for Mouse Enter Event.

MOUSE_EXIT

public static final int MOUSE_EXIT

ID constant for Mouse Exit Event.

MOUSE_MOVE

public static final int MOUSE_MOVE

ID constant for Mouse Move Event.

MOUSE_UP

public static final int MOUSE_UP

ID constant for Mouse Up Event.

NUM_LOCK

public static final int NUM_LOCK

ID constant for Num Lock key.

PAUSE

public static final int PAUSE

ID constant for Pause key.

PGDN

public static final int PGDN

ID constant for PageDown key.

PGUP

public static final int PGUP

ID constant for PageUp key.

PRINT_SCREEN

public static final int PRINT_SCREEN

ID constant for Print Screen key.

RIGHT

public static final int RIGHT

ID constant for the right arrow key.

SAVE_FILE

public static final int SAVE_FILE

ID constant for File Save Event.

SCROLL_ABSOLUTE

public static final int SCROLL_ABSOLUTE

ID constant for Absolute Scroll Event.

SCROLL_BEGIN

public static final int SCROLL_ BEGIN

ID constant for Begin Scroll Event.

SCROLL_END

public static final int SCROLL_ END

ID constant for End Scroll Event.

SCROLL_LINE_DOWN

public static final int SCROLL_LINE_DOWN

ID constant for Line Down Scroll Event.

SCROLL_LINE_UP

public static final int SCROLL_LINE_UP

ID constant for Line Up Scroll Event.

SCROLL_LOCK

public static final int SCROLL_LOCK

Mask for Scroll Lock key.

SCROLL_PAGE_DOWN

public static final int SCROLL_PAGE_DOWN

ID constant for Page Down Scroll Event.

SCROLL_PAGE_UP

public static final int SCROLL_PAGE_UP

ID constant for Page Up Scroll Event.

SHIFT_MASK

public static final int SHIFT_MASK

Mask for SHIFT key.

TAB

public static final int TAB

ID constant for Tab key.

UP

public static final int UP

ID constant for the up arrow key.

WINDOW_DEICONIFY

public static final int WINDOW_DEICONIFY

ID constant for Window DeIconify Event.

WINDOW_DESTROY

public static final int WINDOW_DESTROY

ID constant for Window Destroy Event.

WINDOW_EXPOSE

public static final int WINDOW_EXPOSE

ID constant for Window Expose Event.

WINDOW_ICONIFY

public static final int WINDOW_ICONIFY

ID constant for Window Iconify Event.

WINDOW_MOVED

public static final int WINDOW_MOVED

ID constant for Window Move Event.

Variables

arg

public Object arg

A variable argument that is specific to the event type.

clickCount

public int clickCount

The number of consecutive MOUSE_DOWN events.

evt

public Event evt

A means of passing a linked list of events as one.

id

public int id

The ID constant that identifies the Event type.

key

public int key

Integer value of key pressed, or ID constant identifying a special key.

modifiers

public int modifiers

The state of the shift/alt/control/meta keys, formed by ORing the masks for the appropriate keys.

target

public Object target

The Object that generated the event.

when

public long when

The time the event happened.

x

public int x

The x position at which the event happened.

y

public int y

The y position at which the event happened.

Constructors

Event

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

• Parameters
• • target
  • The component to which the Event should be delivered
  • id
  • The identifier of Event
  • arg
  • The Object that is the cause of the event
• Description
• Constructs an Event object with the given values.

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

• Parameters
• • target
  • The component to which the Event should be delivered
  • when
  • The time the event happened
  • id
  • The identifier of Event
  • x
  • The x position at which the event happened
  • y
  • The y position at which the event happened
  • key
  • Integer value of key pressed, or a constant identifying a special key
  • modifiers
  • The state of the shift/alt/control/meta keys
• Description
• Constructs an Event object with the given values.

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

• Parameters
• • target
  • The component to which the Event should be delivered
  • when
  • The time the event happened
  • id
  • The identifier of Event
  • x
  • The x position at which the event happened
  • y
  • The y position at which the event happened
  • key
  • Integer value of key pressed, or a constant identifying a special key
  • modifiers
  • The state of the shift/alt/control/meta keys
  • arg
  • The Object that is the cause of the event
• Description
• Constructs an Event object with the given values.

Instance Methods

controlDown

public boolean controlDown()

• Returns
• true if the control key was down when the event was triggered, false otherwise.
• Description
• Checks current settings for modifiers of the Event.

metaDown

public boolean metaDown()

• Returns
• true if the meta key was down when the event was triggered, false otherwise.
• Description
• Checks current settings for modifiers of the Event.

shiftDown

public boolean shiftDown()

• Returns
• true if the shift key was down when the event was triggered, false otherwise.
• Description
• Checks current settings for modifiers of the Event.

toString

public String toString()

• Returns
• A string representation of the Event object.
• Overrides
• Object.toString()

translate

public void translate (int x, int y)

• Parameters
• • x
  • Amount to move Event in horizontal direction.
  • y
  • Amount to move Event in vertical direction.
• Description
• Translates x and y coordinates of Event instance by x and y.

Protected Instance Methods

paramString

protected String paramString()

• Returns
• String with current settings of Event.
• Description
• Helper method for toString() to generate string of current settings.

See Also

AWTEvent, Component, Object, String