public class

Button

extends Component
implements Accessible

java.lang.Object
↳	java.awt.Component
	↳	java.awt.Button

Class Overview

This class creates a labeled button. The application can cause some action to happen when the button is pushed. This image depicts three views of a "Quit" button as it appears under the Solaris operating system:

The first view shows the button as it appears normally. The second view shows the button when it has input focus. Its outline is darkened to let the user know that it is an active object. The third view shows the button when the user clicks the mouse over the button, and thus requests that an action be performed.

The gesture of clicking on a button with the mouse is associated with one instance of ActionEvent, which is sent out when the mouse is both pressed and released over the button. If an application is interested in knowing when the button has been pressed but not released, as a separate gesture, it can specialize processMouseEvent, or it can register itself as a listener for mouse events by calling addMouseListener. Both of these methods are defined by Component, the abstract superclass of all components.

When a button is pressed and released, AWT sends an instance of ActionEvent to the button, by calling processEvent on the button. The button's processEvent method receives all events for the button; it passes an action event along by calling its own processActionEvent method. The latter method passes the action event on to any action listeners that have registered an interest in action events generated by this button.

If an application wants to perform some action based on a button being pressed and released, it should implement ActionListener and register the new listener to receive events from this button, by calling the button's addActionListener method. The application can make use of the button's action command as a messaging protocol.

Summary

Nested Classes
class	Button.AccessibleAWTButton	This class implements accessibility support for the `Button` class.

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Inherited Constants

From class java.awt.Component

From interface java.awt.image.ImageObserver

Public Constructors
	Button() Constructs a button with an empty string for its label.
	Button(String label) Constructs a button with the specified label.

Public Methods
synchronized void	addActionListener(ActionListener l) Adds the specified action listener to receive action events from this button.
void	addNotify() Creates the peer of the button.
AccessibleContext	getAccessibleContext() Gets the `AccessibleContext` associated with this `Button`.
String	getActionCommand() Returns the command name of the action event fired by this button.
synchronized ActionListener[]	getActionListeners() Returns an array of all the action listeners registered on this button.
String	getLabel() Gets the label of this button.
<T extends EventListener> T[]	getListeners(Class<T> listenerType) Returns an array of all the objects currently registered as `FooListener`s upon this `Button`.
synchronized void	removeActionListener(ActionListener l) Removes the specified action listener so that it no longer receives action events from this button.
void	setActionCommand(String command) Sets the command name for the action event fired by this button.
void	setLabel(String label) Sets the button's label to be the specified string.

Protected Methods
String	paramString() Returns a string representing the state of this `Button`.
void	processActionEvent(ActionEvent e) Processes action events occurring on this button by dispatching them to any registered `ActionListener` objects.
void	processEvent(AWTEvent e) Processes events on this button.

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Inherited Methods

From class java.awt.Component

boolean	action(Event evt, Object what) This method is deprecated. As of JDK version 1.1, should register this component as ActionListener on component which fires action events.
void	add(PopupMenu popup) Adds the specified popup menu to the component.
synchronized void	addComponentListener(ComponentListener l) Adds the specified component listener to receive component events from this component.
synchronized void	addFocusListener(FocusListener l) Adds the specified focus listener to receive focus events from this component when this component gains input focus.
void	addHierarchyBoundsListener(HierarchyBoundsListener l) Adds the specified hierarchy bounds listener to receive hierarchy bounds events from this component when the hierarchy to which this container belongs changes.
void	addHierarchyListener(HierarchyListener l) Adds the specified hierarchy listener to receive hierarchy changed events from this component when the hierarchy to which this container belongs changes.
synchronized void	addInputMethodListener(InputMethodListener l) Adds the specified input method listener to receive input method events from this component.
synchronized void	addKeyListener(KeyListener l) Adds the specified key listener to receive key events from this component.
synchronized void	addMouseListener(MouseListener l) Adds the specified mouse listener to receive mouse events from this component.
synchronized void	addMouseMotionListener(MouseMotionListener l) Adds the specified mouse motion listener to receive mouse motion events from this component.
synchronized void	addMouseWheelListener(MouseWheelListener l) Adds the specified mouse wheel listener to receive mouse wheel events from this component.
void	addNotify() Makes this `Component` displayable by connecting it to a native screen resource.
void	addPropertyChangeListener(String propertyName, PropertyChangeListener listener) Adds a PropertyChangeListener to the listener list for a specific property.
void	addPropertyChangeListener(PropertyChangeListener listener) Adds a PropertyChangeListener to the listener list.
void	applyComponentOrientation(ComponentOrientation orientation) Sets the `ComponentOrientation` property of this component and all components contained within it.
boolean	areFocusTraversalKeysSet(int id) Returns whether the Set of focus traversal keys for the given focus traversal operation has been explicitly defined for this Component.
Rectangle	bounds() This method is deprecated. As of JDK version 1.1, replaced by `getBounds()`.
int	checkImage(Image image, ImageObserver observer) Returns the status of the construction of a screen representation of the specified image.
int	checkImage(Image image, int width, int height, ImageObserver observer) Returns the status of the construction of a screen representation of the specified image.
AWTEvent	coalesceEvents(AWTEvent existingEvent, AWTEvent newEvent) Potentially coalesce an event being posted with an existing event.
boolean	contains(Point p) Checks whether this component "contains" the specified point, where the point's x and y coordinates are defined to be relative to the coordinate system of this component.
boolean	contains(int x, int y) Checks whether this component "contains" the specified point, where `x` and `y` are defined to be relative to the coordinate system of this component.
Image	createImage(int width, int height) Creates an off-screen drawable image to be used for double buffering.
Image	createImage(ImageProducer producer) Creates an image from the specified image producer.
VolatileImage	createVolatileImage(int width, int height, ImageCapabilities caps) Creates a volatile off-screen drawable image, with the given capabilities.
VolatileImage	createVolatileImage(int width, int height) Creates a volatile off-screen drawable image to be used for double buffering.
void	deliverEvent(Event e) This method is deprecated. As of JDK version 1.1, replaced by `dispatchEvent(AWTEvent e)`.
void	disable() This method is deprecated. As of JDK version 1.1, replaced by `setEnabled(boolean)`.
final void	disableEvents(long eventsToDisable) Disables the events defined by the specified event mask parameter from being delivered to this component.
final void	dispatchEvent(AWTEvent e) Dispatches an event to this component or one of its sub components.
void	doLayout() Prompts the layout manager to lay out this component.
void	enable() This method is deprecated. As of JDK version 1.1, replaced by `setEnabled(boolean)`.
void	enable(boolean b) This method is deprecated. As of JDK version 1.1, replaced by `setEnabled(boolean)`.
final void	enableEvents(long eventsToEnable) Enables the events defined by the specified event mask parameter to be delivered to this component.
void	enableInputMethods(boolean enable) Enables or disables input method support for this component.
void	firePropertyChange(String propertyName, float oldValue, float newValue) Reports a bound property change.
void	firePropertyChange(String propertyName, byte oldValue, byte newValue) Reports a bound property change.
void	firePropertyChange(String propertyName, char oldValue, char newValue) Reports a bound property change.
void	firePropertyChange(String propertyName, short oldValue, short newValue) Reports a bound property change.
void	firePropertyChange(String propertyName, long oldValue, long newValue) Reports a bound property change.
void	firePropertyChange(String propertyName, boolean oldValue, boolean newValue) Support for reporting bound property changes for boolean properties.
void	firePropertyChange(String propertyName, double oldValue, double newValue) Reports a bound property change.
void	firePropertyChange(String propertyName, Object oldValue, Object newValue) Support for reporting bound property changes for Object properties.
void	firePropertyChange(String propertyName, int oldValue, int newValue) Support for reporting bound property changes for integer properties.
AccessibleContext	getAccessibleContext() Gets the `AccessibleContext` associated with this `Component`.
float	getAlignmentX() Returns the alignment along the x axis.
float	getAlignmentY() Returns the alignment along the y axis.
Color	getBackground() Gets the background color of this component.
int	getBaseline(int width, int height) Returns the baseline.
Component.BaselineResizeBehavior	getBaselineResizeBehavior() Returns an enum indicating how the baseline of the component changes as the size changes.
Rectangle	getBounds(Rectangle rv) Stores the bounds of this component into "return value" rv and return rv.
Rectangle	getBounds() Gets the bounds of this component in the form of a `Rectangle` object.
ColorModel	getColorModel() Gets the instance of `ColorModel` used to display the component on the output device.
Component	getComponentAt(Point p) Returns the component or subcomponent that contains the specified point.
Component	getComponentAt(int x, int y) Determines if this component or one of its immediate subcomponents contains the (x, y) location, and if so, returns the containing component.
synchronized ComponentListener[]	getComponentListeners() Returns an array of all the component listeners registered on this component.
ComponentOrientation	getComponentOrientation() Retrieves the language-sensitive orientation that is to be used to order the elements or text within this component.
Cursor	getCursor() Gets the cursor set in the component.
synchronized DropTarget	getDropTarget() Gets the `DropTarget` associated with this `Component`.
Container	getFocusCycleRootAncestor() Returns the Container which is the focus cycle root of this Component's focus traversal cycle.
synchronized FocusListener[]	getFocusListeners() Returns an array of all the focus listeners registered on this component.
Set<AWTKeyStroke>	getFocusTraversalKeys(int id) Returns the Set of focus traversal keys for a given traversal operation for this Component.
boolean	getFocusTraversalKeysEnabled() Returns whether focus traversal keys are enabled for this Component.
Font	getFont() Gets the font of this component.
FontMetrics	getFontMetrics(Font font) Gets the font metrics for the specified font.
Color	getForeground() Gets the foreground color of this component.
Graphics	getGraphics() Creates a graphics context for this component.
GraphicsConfiguration	getGraphicsConfiguration() Gets the `GraphicsConfiguration` associated with this `Component`.
int	getHeight() Returns the current height of this component.
synchronized HierarchyBoundsListener[]	getHierarchyBoundsListeners() Returns an array of all the hierarchy bounds listeners registered on this component.
synchronized HierarchyListener[]	getHierarchyListeners() Returns an array of all the hierarchy listeners registered on this component.
boolean	getIgnoreRepaint()
InputContext	getInputContext() Gets the input context used by this component for handling the communication with input methods when text is entered in this component.
synchronized InputMethodListener[]	getInputMethodListeners() Returns an array of all the input method listeners registered on this component.
InputMethodRequests	getInputMethodRequests() Gets the input method request handler which supports requests from input methods for this component.
synchronized KeyListener[]	getKeyListeners() Returns an array of all the key listeners registered on this component.
<T extends EventListener> T[]	getListeners(Class<T> listenerType) Returns an array of all the objects currently registered as `FooListener`s upon this `Component`.
Locale	getLocale() Gets the locale of this component.
Point	getLocation() Gets the location of this component in the form of a point specifying the component's top-left corner.
Point	getLocation(Point rv) Stores the x,y origin of this component into "return value" rv and return rv.
Point	getLocationOnScreen() Gets the location of this component in the form of a point specifying the component's top-left corner in the screen's coordinate space.
Dimension	getMaximumSize() Gets the maximum size of this component.
Dimension	getMinimumSize() Gets the mininimum size of this component.
synchronized MouseListener[]	getMouseListeners() Returns an array of all the mouse listeners registered on this component.
synchronized MouseMotionListener[]	getMouseMotionListeners() Returns an array of all the mouse motion listeners registered on this component.
Point	getMousePosition() Returns the position of the mouse pointer in this `Component`'s coordinate space if the `Component` is directly under the mouse pointer, otherwise returns `null`.
synchronized MouseWheelListener[]	getMouseWheelListeners() Returns an array of all the mouse wheel listeners registered on this component.
String	getName() Gets the name of the component.
Container	getParent() Gets the parent of this component.
ComponentPeer	getPeer() This method is deprecated. As of JDK version 1.1, programs should not directly manipulate peers; replaced by `boolean isDisplayable()`.
Dimension	getPreferredSize() Gets the preferred size of this component.
PropertyChangeListener[]	getPropertyChangeListeners() Returns an array of all the property change listeners registered on this component.
PropertyChangeListener[]	getPropertyChangeListeners(String propertyName) Returns an array of all the listeners which have been associated with the named property.
Dimension	getSize() Returns the size of this component in the form of a `Dimension` object.
Dimension	getSize(Dimension rv) Stores the width/height of this component into "return value" rv and return rv.
Toolkit	getToolkit() Gets the toolkit of this component.
final Object	getTreeLock() Gets this component's locking object (the object that owns the thread sychronization monitor) for AWT component-tree and layout operations.
int	getWidth() Returns the current width of this component.
int	getX() Returns the current x coordinate of the components origin.
int	getY() Returns the current y coordinate of the components origin.
boolean	gotFocus(Event evt, Object what) This method is deprecated. As of JDK version 1.1, replaced by processFocusEvent(FocusEvent).
boolean	handleEvent(Event evt) This method is deprecated. As of JDK version 1.1 replaced by processEvent(AWTEvent).
boolean	hasFocus() Returns `true` if this `Component` is the focus owner.
void	hide() This method is deprecated. As of JDK version 1.1, replaced by `setVisible(boolean)`.
boolean	imageUpdate(Image img, int infoflags, int x, int y, int w, int h) Repaints the component when the image has changed.
boolean	inside(int x, int y) This method is deprecated. As of JDK version 1.1, replaced by contains(int, int).
void	invalidate() Invalidates this component.
boolean	isBackgroundSet() Returns whether the background color has been explicitly set for this Component.
boolean	isCursorSet() Returns whether the cursor has been explicitly set for this Component.
boolean	isDisplayable() Determines whether this component is displayable.
boolean	isDoubleBuffered() Returns true if this component is painted to an offscreen image ("buffer") that's copied to the screen later.
boolean	isEnabled() Determines whether this component is enabled.
boolean	isFocusCycleRoot(Container container) Returns whether the specified Container is the focus cycle root of this Component's focus traversal cycle.
boolean	isFocusOwner() Returns `true` if this `Component` is the focus owner.
boolean	isFocusTraversable() This method is deprecated. As of 1.4, replaced by `isFocusable()`.
boolean	isFocusable() Returns whether this Component can be focused.
boolean	isFontSet() Returns whether the font has been explicitly set for this Component.
boolean	isForegroundSet() Returns whether the foreground color has been explicitly set for this Component.
boolean	isLightweight() A lightweight component doesn't have a native toolkit peer.
boolean	isMaximumSizeSet() Returns true if the maximum size has been set to a non-`null` value otherwise returns false.
boolean	isMinimumSizeSet() Returns whether or not `setMinimumSize` has been invoked with a non-null value.
boolean	isOpaque() Returns true if this component is completely opaque, returns false by default.
boolean	isPreferredSizeSet() Returns true if the preferred size has been set to a non-`null` value otherwise returns false.
boolean	isShowing() Determines whether this component is showing on screen.
boolean	isValid() Determines whether this component is valid.
boolean	isVisible() Determines whether this component should be visible when its parent is visible.
boolean	keyDown(Event evt, int key) This method is deprecated. As of JDK version 1.1, replaced by processKeyEvent(KeyEvent).
boolean	keyUp(Event evt, int key) This method is deprecated. As of JDK version 1.1, replaced by processKeyEvent(KeyEvent).
void	layout() This method is deprecated. As of JDK version 1.1, replaced by `doLayout()`.
void	list(PrintStream out) Prints a listing of this component to the specified output stream.
void	list() Prints a listing of this component to the standard system output stream `System.out`.
void	list(PrintStream out, int indent) Prints out a list, starting at the specified indentation, to the specified print stream.
void	list(PrintWriter out) Prints a listing to the specified print writer.
void	list(PrintWriter out, int indent) Prints out a list, starting at the specified indentation, to the specified print writer.
Component	locate(int x, int y) This method is deprecated. As of JDK version 1.1, replaced by getComponentAt(int, int).
Point	location() This method is deprecated. As of JDK version 1.1, replaced by `getLocation()`.
boolean	lostFocus(Event evt, Object what) This method is deprecated. As of JDK version 1.1, replaced by processFocusEvent(FocusEvent).
Dimension	minimumSize() This method is deprecated. As of JDK version 1.1, replaced by `getMinimumSize()`.
boolean	mouseDown(Event evt, int x, int y) This method is deprecated. As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
boolean	mouseDrag(Event evt, int x, int y) This method is deprecated. As of JDK version 1.1, replaced by processMouseMotionEvent(MouseEvent).
boolean	mouseEnter(Event evt, int x, int y) This method is deprecated. As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
boolean	mouseExit(Event evt, int x, int y) This method is deprecated. As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
boolean	mouseMove(Event evt, int x, int y) This method is deprecated. As of JDK version 1.1, replaced by processMouseMotionEvent(MouseEvent).
boolean	mouseUp(Event evt, int x, int y) This method is deprecated. As of JDK version 1.1, replaced by processMouseEvent(MouseEvent).
void	move(int x, int y) This method is deprecated. As of JDK version 1.1, replaced by `setLocation(int, int)`.
void	nextFocus() This method is deprecated. As of JDK version 1.1, replaced by transferFocus().
void	paint(Graphics g) Paints this component.
void	paintAll(Graphics g) Paints this component and all of its subcomponents.
String	paramString() Returns a string representing the state of this component.
boolean	postEvent(Event e) This method is deprecated. As of JDK version 1.1, replaced by dispatchEvent(AWTEvent).
Dimension	preferredSize() This method is deprecated. As of JDK version 1.1, replaced by `getPreferredSize()`.
boolean	prepareImage(Image image, ImageObserver observer) Prepares an image for rendering on this component.
boolean	prepareImage(Image image, int width, int height, ImageObserver observer) Prepares an image for rendering on this component at the specified width and height.
void	print(Graphics g) Prints this component.
void	printAll(Graphics g) Prints this component and all of its subcomponents.
void	processComponentEvent(ComponentEvent e) Processes component events occurring on this component by dispatching them to any registered `ComponentListener` objects.
void	processEvent(AWTEvent e) Processes events occurring on this component.
void	processFocusEvent(FocusEvent e) Processes focus events occurring on this component by dispatching them to any registered `FocusListener` objects.
void	processHierarchyBoundsEvent(HierarchyEvent e) Processes hierarchy bounds events occurring on this component by dispatching them to any registered `HierarchyBoundsListener` objects.
void	processHierarchyEvent(HierarchyEvent e) Processes hierarchy events occurring on this component by dispatching them to any registered `HierarchyListener` objects.
void	processInputMethodEvent(InputMethodEvent e) Processes input method events occurring on this component by dispatching them to any registered `InputMethodListener` objects.
void	processKeyEvent(KeyEvent e) Processes key events occurring on this component by dispatching them to any registered `KeyListener` objects.
void	processMouseEvent(MouseEvent e) Processes mouse events occurring on this component by dispatching them to any registered `MouseListener` objects.
void	processMouseMotionEvent(MouseEvent e) Processes mouse motion events occurring on this component by dispatching them to any registered `MouseMotionListener` objects.
void	processMouseWheelEvent(MouseWheelEvent e) Processes mouse wheel events occurring on this component by dispatching them to any registered `MouseWheelListener` objects.
void	remove(MenuComponent popup) Removes the specified popup menu from the component.
synchronized void	removeComponentListener(ComponentListener l) Removes the specified component listener so that it no longer receives component events from this component.
synchronized void	removeFocusListener(FocusListener l) Removes the specified focus listener so that it no longer receives focus events from this component.
void	removeHierarchyBoundsListener(HierarchyBoundsListener l) Removes the specified hierarchy bounds listener so that it no longer receives hierarchy bounds events from this component.
void	removeHierarchyListener(HierarchyListener l) Removes the specified hierarchy listener so that it no longer receives hierarchy changed events from this component.
synchronized void	removeInputMethodListener(InputMethodListener l) Removes the specified input method listener so that it no longer receives input method events from this component.
synchronized void	removeKeyListener(KeyListener l) Removes the specified key listener so that it no longer receives key events from this component.
synchronized void	removeMouseListener(MouseListener l) Removes the specified mouse listener so that it no longer receives mouse events from this component.
synchronized void	removeMouseMotionListener(MouseMotionListener l) Removes the specified mouse motion listener so that it no longer receives mouse motion events from this component.
synchronized void	removeMouseWheelListener(MouseWheelListener l) Removes the specified mouse wheel listener so that it no longer receives mouse wheel events from this component.
void	removeNotify() Makes this `Component` undisplayable by destroying it native screen resource.
void	removePropertyChangeListener(String propertyName, PropertyChangeListener listener) Removes a `PropertyChangeListener` from the listener list for a specific property.
void	removePropertyChangeListener(PropertyChangeListener listener) Removes a PropertyChangeListener from the listener list.
void	repaint(int x, int y, int width, int height) Repaints the specified rectangle of this component.
void	repaint(long tm, int x, int y, int width, int height) Repaints the specified rectangle of this component within `tm` milliseconds.
void	repaint() Repaints this component.
void	repaint(long tm) Repaints the component.
void	requestFocus() Requests that this Component get the input focus, and that this Component's top-level ancestor become the focused Window.
boolean	requestFocus(boolean temporary) Requests that this `Component` get the input focus, and that this `Component`'s top-level ancestor become the focused `Window`.
boolean	requestFocusInWindow(boolean temporary) Requests that this `Component` get the input focus, if this `Component`'s top-level ancestor is already the focused `Window`.
boolean	requestFocusInWindow() Requests that this Component get the input focus, if this Component's top-level ancestor is already the focused Window.
void	reshape(int x, int y, int width, int height) This method is deprecated. As of JDK version 1.1, replaced by `setBounds(int, int, int, int)`.
void	resize(Dimension d) This method is deprecated. As of JDK version 1.1, replaced by `setSize(Dimension)`.
void	resize(int width, int height) This method is deprecated. As of JDK version 1.1, replaced by `setSize(int, int)`.
void	setBackground(Color c) Sets the background color of this component.
void	setBounds(int x, int y, int width, int height) Moves and resizes this component.
void	setBounds(Rectangle r) Moves and resizes this component to conform to the new bounding rectangle `r`.
void	setComponentOrientation(ComponentOrientation o) Sets the language-sensitive orientation that is to be used to order the elements or text within this component.
void	setCursor(Cursor cursor) Sets the cursor image to the specified cursor.
synchronized void	setDropTarget(DropTarget dt) Associate a `DropTarget` with this component.
void	setEnabled(boolean b) Enables or disables this component, depending on the value of the parameter `b`.
void	setFocusTraversalKeys(int id, Set<? extends AWTKeyStroke> keystrokes) Sets the focus traversal keys for a given traversal operation for this Component.
void	setFocusTraversalKeysEnabled(boolean focusTraversalKeysEnabled) Sets whether focus traversal keys are enabled for this Component.
void	setFocusable(boolean focusable) Sets the focusable state of this Component to the specified value.
void	setFont(Font f) Sets the font of this component.
void	setForeground(Color c) Sets the foreground color of this component.
void	setIgnoreRepaint(boolean ignoreRepaint) Sets whether or not paint messages received from the operating system should be ignored.
void	setLocale(Locale l) Sets the locale of this component.
void	setLocation(int x, int y) Moves this component to a new location.
void	setLocation(Point p) Moves this component to a new location.
void	setMaximumSize(Dimension maximumSize) Sets the maximum size of this component to a constant value.
void	setMinimumSize(Dimension minimumSize) Sets the minimum size of this component to a constant value.
void	setName(String name) Sets the name of the component to the specified string.
void	setPreferredSize(Dimension preferredSize) Sets the preferred size of this component to a constant value.
void	setSize(int width, int height) Resizes this component so that it has width `width` and height `height`.
void	setSize(Dimension d) Resizes this component so that it has width `d.width` and height `d.height`.
void	setVisible(boolean b) Shows or hides this component depending on the value of parameter `b`.
void	show() This method is deprecated. As of JDK version 1.1, replaced by `setVisible(boolean)`.
void	show(boolean b) This method is deprecated. As of JDK version 1.1, replaced by `setVisible(boolean)`.
Dimension	size() This method is deprecated. As of JDK version 1.1, replaced by `getSize()`.
String	toString() Returns a string representation of this component and its values.
void	transferFocus() Transfers the focus to the next component, as though this Component were the focus owner.
void	transferFocusBackward() Transfers the focus to the previous component, as though this Component were the focus owner.
void	transferFocusUpCycle() Transfers the focus up one focus traversal cycle.
void	update(Graphics g) Updates this component.
void	validate() Ensures that this component has a valid layout.

From class java.lang.Object

Object	clone() Creates and returns a copy of this object.
boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
void	finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
final Class<?>	getClass() Returns the runtime class of this `Object`.
int	hashCode() Returns a hash code value for the object.
final void	notify() Wakes up a single thread that is waiting on this object's monitor.
final void	notifyAll() Wakes up all threads that are waiting on this object's monitor.
String	toString() Returns a string representation of the object.
final void	wait() Causes the current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object.
final void	wait(long timeout, int nanos) Causes the current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.
final void	wait(long timeout) Causes the current thread to wait until either another thread invokes the `notify()` method or the `notifyAll()` method for this object, or a specified amount of time has elapsed.

From interface java.awt.MenuContainer

From interface java.awt.image.ImageObserver

From interface javax.accessibility.Accessible

Public Constructors

public Button ()

Constructs a button with an empty string for its label.

Throws

HeadlessException	if GraphicsEnvironment.isHeadless() returns true

public Button (String label)

Constructs a button with the specified label.

Parameters

label	a string label for the button, or `null` for no label

Throws

HeadlessException	if GraphicsEnvironment.isHeadless() returns true

Public Methods

public synchronized void addActionListener (ActionListener l)

Adds the specified action listener to receive action events from this button. Action events occur when a user presses or releases the mouse over this button. If l is null, no exception is thrown and no action is performed.

Refer to AWT Threading Issues for details on AWT's threading model.

Parameters

l	the action listener

public void addNotify ()

Creates the peer of the button. The button's peer allows the application to change the look of the button without changing its functionality.

public AccessibleContext getAccessibleContext ()

Gets the AccessibleContext associated with this Button. For buttons, the AccessibleContext takes the form of an AccessibleAWTButton. A new AccessibleAWTButton instance is created if necessary.

Returns

an AccessibleAWTButton that serves as the AccessibleContext of this Button

public String getActionCommand ()

Returns the command name of the action event fired by this button. If the command name is null (default) then this method returns the label of the button.

public synchronized ActionListener[] getActionListeners ()

Returns an array of all the action listeners registered on this button.

Returns

all of this button's ActionListeners or an empty array if no action listeners are currently registered

public String getLabel ()

Gets the label of this button.

Returns

the button's label, or null if the button has no label.

public T[] getListeners (Class<T> listenerType)

Returns an array of all the objects currently registered as FooListeners upon this Button. FooListeners are registered using the addFooListener method.

You can specify the listenerType argument with a class literal, such as FooListener.class. For example, you can query a Button b for its action listeners with the following code:

ActionListener[] als = (ActionListener[])(b.getListeners(ActionListener.class));

If no such listeners exist, this method returns an empty array.

Parameters

listenerType	the type of listeners requested; this parameter should specify an interface that descends from `java.util.EventListener`

Returns

an array of all objects registered as FooListeners on this button, or an empty array if no such listeners have been added

Throws

ClassCastException	if `listenerType` doesn't specify a class or interface that implements `java.util.EventListener`

public synchronized void removeActionListener (ActionListener l)

Removes the specified action listener so that it no longer receives action events from this button. Action events occur when a user presses or releases the mouse over this button. If l is null, no exception is thrown and no action is performed.

Refer to AWT Threading Issues for details on AWT's threading model.

Parameters

l	the action listener

public void setActionCommand (String command)

Sets the command name for the action event fired by this button. By default this action command is set to match the label of the button.

Parameters

command	a string used to set the button's action command. If the string is `null` then the action command is set to match the label of the button.

public void setLabel (String label)

Sets the button's label to be the specified string.

Parameters

label	the new label, or `null` if the button has no label.

Protected Methods

protected String paramString ()

Returns a string representing the state of this Button. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null.

Returns

the parameter string of this button

protected void processActionEvent (ActionEvent e)

Processes action events occurring on this button by dispatching them to any registered ActionListener objects.

This method is not called unless action events are enabled for this button. Action events are enabled when one of the following occurs:

An ActionListener object is registered via addActionListener.
Action events are enabled via enableEvents.

Note that if the event parameter is null the behavior is unspecified and may result in an exception.

Parameters

e	the action event

protected void processEvent (AWTEvent e)

Processes events on this button. If an event is an instance of ActionEvent, this method invokes the processActionEvent method. Otherwise, it invokes processEvent on the superclass.

Note that if the event parameter is null the behavior is unspecified and may result in an exception.

Parameters

e	the event

Interfaces

Classes

Enums

Exceptions

Errors

Button

Class Overview

See Also

Summary

Public Constructors

public Button ()

Throws

See Also

public Button (String label)

Parameters

Throws

See Also

Public Methods

public synchronized void addActionListener (ActionListener l)

Parameters

See Also

public void addNotify ()

See Also

public AccessibleContext getAccessibleContext ()

Returns

public String getActionCommand ()

public synchronized ActionListener[] getActionListeners ()

Returns

See Also

public String getLabel ()

Returns

See Also

public T[] getListeners (Class<T> listenerType)

Parameters

Returns

Throws

See Also

public synchronized void removeActionListener (ActionListener l)

Parameters

See Also

public void setActionCommand (String command)

Parameters

See Also

public void setLabel (String label)

Parameters

See Also

Protected Methods

protected String paramString ()

Returns

protected void processActionEvent (ActionEvent e)

Parameters

See Also

protected void processEvent (AWTEvent e)

Parameters

See Also