OpenJDK 27 · java.awt.event.ComponentEvent · APIdia, the JavaDoc alternative

A low-level event which indicates that a component moved, changed size, or changed visibility (also, the root class for the other component-level events).

Component events are provided for notification purposes ONLY; The AWT will automatically handle component moves and resizes internally so that GUI layout works properly regardless of whether a program is receiving these events or not.

In addition to serving as the base class for other component-related events (InputEvent, FocusEvent, WindowEvent, ContainerEvent), this class defines the events that indicate changes in a component's size, position, or visibility.

This low-level event is generated by a component object (such as a List) when the component is moved, resized, rendered invisible, or made visible again. The event is passed to every ComponentListener or ComponentAdapter object which registered to receive such events using the component's addComponentListener method. (ComponentAdapter objects implement the ComponentListener interface.) Each such listener object gets this ComponentEvent when the event occurs.

An unspecified behavior will be caused if the id parameter of any particular ComponentEvent instance is not in the range from COMPONENT_FIRST to COMPONENT_LAST.

Field Summary

Modifier and Type	Field and Description
public static final int	COMPONENT_FIRST The first number in the range of ids used for component events.
public static final int	COMPONENT_HIDDEN This event indicates that the component was rendered invisible.
public static final int	COMPONENT_LAST The last number in the range of ids used for component events.
public static final int	COMPONENT_MOVED This event indicates that the component's position changed.
public static final int	COMPONENT_RESIZED This event indicates that the component's size changed.
public static final int	COMPONENT_SHOWN This event indicates that the component was made visible.
private static final long	serialVersionUID Hides java.awt.AWTEvent.serialVersionUID. Use serialVersionUID from JDK 1.1 for interoperability.

Constructor Summary

Access	Constructor and Description
public	ComponentEvent(Component The `Component` that originated the event source, int An integer indicating the type of event. For information on allowable values, see the class description for `ComponentEvent` id) Constructs a `ComponentEvent` object.

Method Summary

Modifier and Type	Method and Description
public Component	Returns: the `Component` object that originated the event, or `null` if the object is not a `Component`. getComponent() Returns the originator of the event.
public String	Returns: a string identifying the event and its attributes paramString() Overrides java.awt.AWTEvent.paramString. Returns a parameter string identifying this event.

Inherited from java.awt.AWTEvent:: consume getID isConsumed setSource toString

Field Detail

COMPONENT_FIRST	back to summary
public static final int COMPONENT_FIRST The first number in the range of ids used for component events.

COMPONENT_HIDDEN	back to summary
public static final int COMPONENT_HIDDEN This event indicates that the component was rendered invisible. Annotations @Native

COMPONENT_LAST	back to summary
public static final int COMPONENT_LAST The last number in the range of ids used for component events.

COMPONENT_MOVED	back to summary
public static final int COMPONENT_MOVED This event indicates that the component's position changed. Annotations @Native

COMPONENT_RESIZED	back to summary
public static final int COMPONENT_RESIZED This event indicates that the component's size changed. Annotations @Native

COMPONENT_SHOWN	back to summary
public static final int COMPONENT_SHOWN This event indicates that the component was made visible. Annotations @Native

serialVersionUID	back to summary
private static final long serialVersionUID Hides java.awt.AWTEvent.serialVersionUID. Use serialVersionUID from JDK 1.1 for interoperability. Annotations @Serial

serialVersionUID

back to summary

private static final long serialVersionUID

Hides java.awt.AWTEvent.serialVersionUID.

Use serialVersionUID from JDK 1.1 for interoperability.

Annotations

@Serial

Constructor Detail

ComponentEvent back to summary

ComponentEvent	back to summary
public ComponentEvent(Component source, int id) Constructs a `ComponentEvent` object. This method throws an `IllegalArgumentException` if `source` is `null`. Parameters source:Component The `Component` that originated the event id:int An integer indicating the type of event. For information on allowable values, see the class description for `ComponentEvent` Exceptions IllegalArgumentException: if `source` is null See Also `getComponent()`, `getID()`

public ComponentEvent(Component source, int id)

Constructs a ComponentEvent object.

This method throws an IllegalArgumentException if source is null.

Parameters

source:Component: The Component that originated the event
id:int: An integer indicating the type of event. For information on allowable values, see the class description for ComponentEvent

Exceptions

IllegalArgumentException:: if source is null

See Also

getComponent(), getID()

Method Detail

getComponent back to summary

getComponent	back to summary
public Component getComponent() Returns the originator of the event. Returns:Component the `Component` object that originated the event, or `null` if the object is not a `Component`.

public Component getComponent()

Returns the originator of the event.

Returns:Component: the Component object that originated the event, or null if the object is not a Component.

paramString	back to summary
public String paramString() Overrides java.awt.AWTEvent.paramString. Returns a parameter string identifying this event. This method is useful for event-logging and for debugging. Returns:String a string identifying the event and its attributes

paramString

back to summary

public String paramString()

Overrides java.awt.AWTEvent.paramString.

Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.