Class DefaultButtonModel

java.lang.Object
javax.swing.DefaultButtonModel
All Implemented Interfaces:
ItemSelectable, Serializable, ButtonModel
Direct Known Subclasses:
JToggleButton.ToggleButtonModel
public class DefaultButtonModel extends Object implements ButtonModel, Serializable
The default implementation of a Button component's data model.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans has been added to the java.beans package. Please see XMLEncoder.

Since:
1.2

Field Summary

Modifier and Type Field Description
protected String actionCommand
The action command string fired by the button.
static final int ARMED
Identifies the "armed" bit in the bitmask, which indicates partial commitment towards choosing/triggering the button.
protected ChangeEvent changeEvent
Only one ChangeEvent is needed per button model instance since the event's only state is the source property.
static final int ENABLED
Identifies the "enabled" bit in the bitmask, which indicates that the button can be selected by an input device (such as a mouse pointer).
protected ButtonGroup group
The button group that the button belongs to.
protected EventListenerList listenerList
Stores the listeners on this model.
protected int mnemonic
The button's mnemonic.
static final int PRESSED
Identifies the "pressed" bit in the bitmask, which indicates that the button is pressed.
static final int ROLLOVER
Identifies the "rollover" bit in the bitmask, which indicates that the mouse is over the button.
static final int SELECTED
Identifies the "selected" bit in the bitmask, which indicates that the button has been selected.
protected int stateMask
The bitmask used to store the state of the button.

Constructor Summary

Constructor Description
DefaultButtonModel()
Constructs a DefaultButtonModel.

Method Summary

Modifier and Type Method Description
void addActionListener(ActionListener l)
Adds an ActionListener to the model.
void addChangeListener(ChangeListener l)
Adds a ChangeListener to the model.
void addItemListener(ItemListener l)
Adds an ItemListener to the model.
protected void fireActionPerformed(ActionEvent e)
Notifies all listeners that have registered interest for notification on this event type.
protected void fireItemStateChanged(ItemEvent e)
Notifies all listeners that have registered interest for notification on this event type.
protected void fireStateChanged()
Notifies all listeners that have registered interest for notification on this event type.
String getActionCommand()
Returns the action command string for the button.
ActionListener[] getActionListeners()
Returns an array of all the action listeners registered on this DefaultButtonModel.
ChangeListener[] getChangeListeners()
Returns an array of all the change listeners registered on this DefaultButtonModel.
ButtonGroup getGroup()
Returns the group that the button belongs to.
ItemListener[] getItemListeners()
Returns an array of all the item listeners registered on this DefaultButtonModel.
<T extends EventListener>
T[]
getListeners(Class<T> listenerType)
Returns an array of all the objects currently registered as FooListeners upon this model.
int getMnemonic()
Gets the keyboard mnemonic for the button.
Object[] getSelectedObjects()
Overridden to return null.
boolean isArmed()
Indicates partial commitment towards triggering the button.
boolean isEnabled()
Indicates if the button can be selected or triggered by an input device, such as a mouse pointer.
boolean isPressed()
Indicates if the button is pressed.
boolean isRollover()
Indicates that the mouse is over the button.
boolean isSelected()
Indicates if the button has been selected.
void removeActionListener(ActionListener l)
Removes an ActionListener from the model.
void removeChangeListener(ChangeListener l)
Removes a ChangeListener from the model.
void removeItemListener(ItemListener l)
Removes an ItemListener from the model.
void setActionCommand(String actionCommand)
Sets the action command string that gets sent as part of the ActionEvent when the button is triggered.
void setArmed(boolean b)
Marks the button as armed or unarmed.
void setEnabled(boolean b)
Enables or disables the button.
void setGroup(ButtonGroup group)
Identifies the group the button belongs to -- needed for radio buttons, which are mutually exclusive within their group.
void setMnemonic(int key)
Sets the keyboard mnemonic (shortcut key or accelerator key) for the button.
void setPressed(boolean b)
Sets the button to pressed or unpressed.
void setRollover(boolean b)
Sets or clears the button's rollover state
void setSelected(boolean b)
Selects or deselects the button.

Methods declared in class java.lang.Object

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

Field Details

stateMask

protected int stateMask
The bitmask used to store the state of the button.

actionCommand

protected String actionCommand
The action command string fired by the button.

group

protected ButtonGroup group
The button group that the button belongs to.

mnemonic

protected int mnemonic
The button's mnemonic.

changeEvent

protected transient ChangeEvent changeEvent
Only one ChangeEvent is needed per button model instance since the event's only state is the source property. The source of events generated is always "this".

listenerList

protected EventListenerList listenerList
Stores the listeners on this model.

ARMED

public static final int ARMED
Identifies the "armed" bit in the bitmask, which indicates partial commitment towards choosing/triggering the button.
See Also:

SELECTED

public static final int SELECTED
Identifies the "selected" bit in the bitmask, which indicates that the button has been selected. Only needed for certain types of buttons - such as radio button or check box.
See Also:

PRESSED

public static final int PRESSED
Identifies the "pressed" bit in the bitmask, which indicates that the button is pressed.
See Also:

ENABLED

public static final int ENABLED
Identifies the "enabled" bit in the bitmask, which indicates that the button can be selected by an input device (such as a mouse pointer).
See Also:

ROLLOVER

public static final int ROLLOVER
Identifies the "rollover" bit in the bitmask, which indicates that the mouse is over the button.
See Also:

Constructor Details

DefaultButtonModel

public DefaultButtonModel()
Constructs a DefaultButtonModel.

Method Details

setActionCommand

public void setActionCommand(String actionCommand)
Sets the action command string that gets sent as part of the ActionEvent when the button is triggered.
Specified by:
setActionCommand in interface ButtonModel
Parameters:
actionCommand - the String that identifies the generated event
See Also:

getActionCommand

public String getActionCommand()
Returns the action command string for the button.
Specified by:
getActionCommand in interface ButtonModel
Returns:
the String that identifies the generated event
See Also:

isArmed

public boolean isArmed()
Indicates partial commitment towards triggering the button.
Specified by:
isArmed in interface ButtonModel
Returns:
true if the button is armed, and ready to be triggered
See Also:

isSelected

public boolean isSelected()
Indicates if the button has been selected. Only needed for certain types of buttons - such as radio buttons and check boxes.
Specified by:
isSelected in interface ButtonModel
Returns:
true if the button is selected

isEnabled

public boolean isEnabled()
Indicates if the button can be selected or triggered by an input device, such as a mouse pointer.
Specified by:
isEnabled in interface ButtonModel
Returns:
true if the button is enabled

isPressed

public boolean isPressed()
Indicates if the button is pressed.
Specified by:
isPressed in interface ButtonModel
Returns:
true if the button is pressed

isRollover

public boolean isRollover()
Indicates that the mouse is over the button.
Specified by:
isRollover in interface ButtonModel
Returns:
true if the mouse is over the button

setArmed

public void setArmed(boolean b)
Marks the button as armed or unarmed.
Specified by:
setArmed in interface ButtonModel
Parameters:
b - whether or not the button should be armed

setEnabled

public void setEnabled(boolean b)
Enables or disables the button.
Specified by:
setEnabled in interface ButtonModel
Parameters:
b - whether or not the button should be enabled
See Also:

setSelected

public void setSelected(boolean b)
Selects or deselects the button.
Specified by:
setSelected in interface ButtonModel
Parameters:
b - true selects the button, false deselects the button

setPressed

public void setPressed(boolean b)
Sets the button to pressed or unpressed.
Specified by:
setPressed in interface ButtonModel
Parameters:
b - whether or not the button should be pressed
See Also:

setRollover

public void setRollover(boolean b)
Sets or clears the button's rollover state
Specified by:
setRollover in interface ButtonModel
Parameters:
b - whether or not the button is in the rollover state
See Also:

setMnemonic

public void setMnemonic(int key)
Sets the keyboard mnemonic (shortcut key or accelerator key) for the button.
Specified by:
setMnemonic in interface ButtonModel
Parameters:
key - an int specifying the accelerator key

getMnemonic

public int getMnemonic()
Gets the keyboard mnemonic for the button.
Specified by:
getMnemonic in interface ButtonModel
Returns:
an int specifying the accelerator key
See Also:

addChangeListener

public void addChangeListener(ChangeListener l)
Adds a ChangeListener to the model.
Specified by:
addChangeListener in interface ButtonModel
Parameters:
l - the listener to add

removeChangeListener

public void removeChangeListener(ChangeListener l)
Removes a ChangeListener from the model.
Specified by:
removeChangeListener in interface ButtonModel
Parameters:
l - the listener to remove

getChangeListeners

public ChangeListener[] getChangeListeners()
Returns an array of all the change listeners registered on this DefaultButtonModel.
Returns:
all of this model's ChangeListeners or an empty array if no change listeners are currently registered
Since:
1.4
See Also:

fireStateChanged

protected void fireStateChanged()
Notifies all listeners that have registered interest for notification on this event type. The event instance is created lazily.
See Also:

addActionListener

public void addActionListener(ActionListener l)
Adds an ActionListener to the model.
Specified by:
addActionListener in interface ButtonModel
Parameters:
l - the listener to add

removeActionListener

public void removeActionListener(ActionListener l)
Removes an ActionListener from the model.
Specified by:
removeActionListener in interface ButtonModel
Parameters:
l - the listener to remove

getActionListeners

public ActionListener[] getActionListeners()
Returns an array of all the action listeners registered on this DefaultButtonModel.
Returns:
all of this model's ActionListeners or an empty array if no action listeners are currently registered
Since:
1.4
See Also:

fireActionPerformed

protected void fireActionPerformed(ActionEvent e)
Notifies all listeners that have registered interest for notification on this event type.
Parameters:
e - the ActionEvent to deliver to listeners
See Also:

addItemListener

public void addItemListener(ItemListener l)
Adds an ItemListener to the model.
Specified by:
addItemListener in interface ButtonModel
Specified by:
addItemListener in interface ItemSelectable
Parameters:
l - the listener to add
See Also:

removeItemListener

public void removeItemListener(ItemListener l)
Removes an ItemListener from the model.
Specified by:
removeItemListener in interface ButtonModel
Specified by:
removeItemListener in interface ItemSelectable
Parameters:
l - the listener to remove
See Also:

getItemListeners

public ItemListener[] getItemListeners()
Returns an array of all the item listeners registered on this DefaultButtonModel.
Returns:
all of this model's ItemListeners or an empty array if no item listeners are currently registered
Since:
1.4
See Also:

fireItemStateChanged

protected void fireItemStateChanged(ItemEvent e)
Notifies all listeners that have registered interest for notification on this event type.
Parameters:
e - the ItemEvent to deliver to listeners
See Also:

getListeners

public <T extends EventListener> T[] getListeners(Class<T> listenerType)
Returns an array of all the objects currently registered as FooListeners upon this model. 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 DefaultButtonModel instance m for its action listeners with the following code:

ActionListener[] als = (ActionListener[])(m.getListeners(ActionListener.class));
If no such listeners exist, this method returns an empty array.
Type Parameters:
T - the type of requested listeners
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 model, 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
Since:
1.3
See Also:

getSelectedObjects

public Object[] getSelectedObjects()
Overridden to return null.
Specified by:
getSelectedObjects in interface ItemSelectable
Returns:
the list of selected objects, or null

setGroup

public void setGroup(ButtonGroup group)
Identifies the group the button belongs to -- needed for radio buttons, which are mutually exclusive within their group.
Specified by:
setGroup in interface ButtonModel
Parameters:
group - the ButtonGroup the button belongs to

getGroup

public ButtonGroup getGroup()
Returns the group that the button belongs to. Normally used with radio buttons, which are mutually exclusive within their group.
Specified by:
getGroup in interface ButtonModel
Returns:
the ButtonGroup that the button belongs to
Since:
1.3

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https://docs.oracle.com/en/java/javase/17/docs/api/java.desktop/javax/swing/DefaultButtonModel.html