public class

JButton

extends AbstractButton
implements Accessible
java.lang.Object
   ↳ java.awt.Component
     ↳ java.awt.Container
       ↳ javax.swing.JComponent
         ↳ javax.swing.AbstractButton
           ↳ javax.swing.JButton
Known Direct Subclasses
Known Indirect Subclasses

Class Overview

An implementation of a "push" button.

Buttons can be configured, and to some degree controlled, by Actions. Using an Action with a button has many benefits beyond directly configuring a button. Refer to Swing Components Supporting Action for more details, and you can find more information in How to Use Actions, a section in The Java Tutorial.

See How to Use Buttons, Check Boxes, and Radio Buttons in The Java Tutorial for information and examples of using buttons.

Warning: Swing is not thread safe. For more information see Swing's Threading Policy.

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 JavaBeansTM has been added to the java.beans package. Please see XMLEncoder.

Summary

Nested Classes
class JButton.AccessibleJButton This class implements accessibility support for the JButton class. 
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Inherited Constants
From class javax.swing.AbstractButton
From class javax.swing.JComponent
From class java.awt.Component
From interface java.awt.image.ImageObserver
From interface javax.swing.SwingConstants
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Inherited Fields
From class javax.swing.AbstractButton
From class javax.swing.JComponent
Public Constructors
JButton()
Creates a button with no set text or icon.
JButton(Icon icon)
Creates a button with an icon.
JButton(String text)
Creates a button with text.
JButton(Action a)
Creates a button where properties are taken from the Action supplied.
JButton(String text, Icon icon)
Creates a button with initial text and an icon.
Public Methods
AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this JButton.
String getUIClassID()
Returns a string that specifies the name of the L&F class that renders this component.
boolean isDefaultButton()
Gets the value of the defaultButton property, which if true means that this button is the current default button for its JRootPane.
boolean isDefaultCapable()
Gets the value of the defaultCapable property.
void removeNotify()
Overrides JComponent.removeNotify to check if this button is currently set as the default button on the RootPane, and if so, sets the RootPane's default button to null to ensure the RootPane doesn't hold onto an invalid button reference.
void setDefaultCapable(boolean defaultCapable)
Sets the defaultCapable property, which determines whether this button can be made the default button for its root pane.
void updateUI()
Resets the UI property to a value from the current look and feel.
Protected Methods
String paramString()
Returns a string representation of this JButton.
[Expand]
Inherited Methods
From class javax.swing.AbstractButton
From class javax.swing.JComponent
From class java.awt.Container
From class java.awt.Component
From class java.lang.Object
From interface java.awt.ItemSelectable
From interface java.awt.MenuContainer
From interface java.awt.image.ImageObserver
From interface javax.accessibility.Accessible

Public Constructors

public JButton ()

Creates a button with no set text or icon.

public JButton (Icon icon)

Creates a button with an icon.

Parameters
icon the Icon image to display on the button

public JButton (String text)

Creates a button with text.

Parameters
text the text of the button

public JButton (Action a)

Creates a button where properties are taken from the Action supplied.

Parameters
a the Action used to specify the new button

public JButton (String text, Icon icon)

Creates a button with initial text and an icon.

Parameters
text the text of the button
icon the Icon image to display on the button

Public Methods

public AccessibleContext getAccessibleContext ()

Gets the AccessibleContext associated with this JButton. For JButtons, the AccessibleContext takes the form of an AccessibleJButton. A new AccessibleJButton instance is created if necessary.

Returns
  • an AccessibleJButton that serves as the AccessibleContext of this JButton

public String getUIClassID ()

Returns a string that specifies the name of the L&F class that renders this component.

Returns
  • the string "ButtonUI"

public boolean isDefaultButton ()

Gets the value of the defaultButton property, which if true means that this button is the current default button for its JRootPane. Most look and feels render the default button differently, and may potentially provide bindings to access the default button.

Returns
  • the value of the defaultButton property

public boolean isDefaultCapable ()

Gets the value of the defaultCapable property.

Returns
  • the value of the defaultCapable property

public void removeNotify ()

Overrides JComponent.removeNotify to check if this button is currently set as the default button on the RootPane, and if so, sets the RootPane's default button to null to ensure the RootPane doesn't hold onto an invalid button reference.

public void setDefaultCapable (boolean defaultCapable)

Sets the defaultCapable property, which determines whether this button can be made the default button for its root pane. The default value of the defaultCapable property is true unless otherwise specified by the look and feel.

Parameters
defaultCapable true if this button will be capable of being the default button on the RootPane; otherwise false

public void updateUI ()

Resets the UI property to a value from the current look and feel.

See Also

Protected Methods

protected String paramString ()

Returns a string representation of this JButton. 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
  • a string representation of this JButton