Class FocusAdapter

java.lang.Object

java.awt.event.FocusAdapter

All Implemented Interfaces:: FocusListener, EventListener

Direct Known Subclasses:: BasicSplitPaneUI.FocusHandler, BasicTabbedPaneUI.FocusHandler

public abstract class FocusAdapter extends Object implements FocusListener

An abstract adapter class for receiving keyboard focus events. The methods in this class are empty. This class exists as convenience for creating listener objects.

Extend this class to create a FocusEvent listener and override the methods for the events of interest. (If you implement the FocusListener interface, you have to define all of the methods in it. This abstract class defines null methods for them all, so you can only have to define methods for events you care about.)

Create a listener object using the extended class and then register it with a component using the component's addFocusListener method. When the component gains or loses the keyboard focus, the relevant method in the listener object is invoked, and the FocusEvent is passed to it.

Since:

1.1

See Also:

Constructor Summary

FocusAdapter()

Modifier	Constructor	Description
`protected`	Constructs a `FocusAdapter`.

Method Summary

Modifier and Type	Method	Description
`void`	`focusGained(FocusEvent e)`	Invoked when a component gains the keyboard focus.
`void`	`focusLost(FocusEvent e)`	Invoked when a component loses the keyboard focus.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this 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 it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

FocusAdapter

protected FocusAdapter()

Constructs a FocusAdapter.

Method Details

focusGained

public void focusGained(FocusEvent e)

Invoked when a component gains the keyboard focus.

Specified by:: focusGained in interface FocusListener
Parameters:: e - the event to be processed

focusLost

public void focusLost(FocusEvent e)

Invoked when a component loses the keyboard focus.

Specified by:: focusLost in interface FocusListener
Parameters:: e - the event to be processed

© 1993, 2025, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.