Top Description Inners Fields Constructors Methods

java.awt

public Class Label

Class Inheritance

extends Component
implements Accessible

All Implemented Interfaces

javax.accessibility.Accessible

Imports

java.awt.peer.LabelPeer, java.io.IOException, .ObjectInputStream, .Serial, javax.accessibility.Accessible, .AccessibleContext, .AccessibleRole

A Label object is a component for placing text in a container. A label displays a single line of read-only text. The text can be changed by the application, but a user cannot edit it directly.

For example, the code . . .

setLayout(new FlowLayout(FlowLayout.CENTER, 10, 10));
add(new Label("Hi There!"));
add(new Label("Another Label"));

produces the following labels:

Two labels: 'Hi There!' and
'Another label'

Author: Sami Shaio
Since: 1.0

Nested and Inner Type Summary

Modifier and Type	Class and Description
protected class	Label.AccessibleAWTLabel This class implements accessibility support for the `Label` class.

Field Summary

Modifier and Type	Field and Description
pack-priv int	alignment The label's alignment.
private static final String	base
public static final int	CENTER Indicates that the label should be centered.
public static final int	LEFT Indicates that the label should be left justified.
private static int	nameCounter
public static final int	RIGHT Indicates that the label should be right justified.
private static final long	serialVersionUID Hides java.awt.Component.serialVersionUID. Use serialVersionUID from JDK 1.1 for interoperability.
pack-priv String	text The text of this label.

Inherited from java.awt.Component:: accessibleContext actionListenerK adjustmentListenerK background backgroundEraseDisabled BOTTOM_ALIGNMENT CENTER_ALIGNMENT componentListener componentListenerK componentOrientation containerListenerK cursor dropTarget enabled eventCache eventMask focusListener focusListenerK focusTraversalKeys font foreground height hierarchyBoundsListener hierarchyBoundsListenerK hierarchyListener hierarchyListenerK ignoreRepaint incRate inputMethodListener inputMethodListenerK isInc isPacked itemListenerK keyListener keyListenerK LEFT_ALIGNMENT locale LOCK maxSize maxSizeSet minSize minSizeSet mouseListener mouseListenerK mouseMotionListener mouseMotionListenerK mouseWheelListener mouseWheelListenerK newEventsOnly ownedWindowK parent peer peerFont popups prefSize prefSizeSet RIGHT_ALIGNMENT textListenerK TOP_ALIGNMENT visible width windowFocusListenerK windowListenerK windowStateListenerK x y

Constructor Summary

Access	Constructor and Description
public	Label() Constructs an empty label.
public	Label(String the string that the label presents. A `null` value will be accepted without causing a NullPointerException to be thrown. text) Constructs a new label with the specified string of text, left justified.
public	Label(String the string that the label presents. A `null` value will be accepted without causing a NullPointerException to be thrown. text, int the alignment value. alignment) Constructs a new label that presents the specified string of text with the specified alignment.

Method Summary

Modifier and Type	Method and Description
public void	addNotify() Overrides java.awt.Component.addNotify. Creates the peer for this label.
pack-priv String	constructComponentName() Overrides java.awt.Component.constructComponentName. Construct a name for this component.
public AccessibleContext	Returns: an AccessibleAWTLabel that serves as the AccessibleContext of this Label getAccessibleContext() Overrides java.awt.Component.getAccessibleContext. Implements javax.accessibility.Accessible.getAccessibleContext. Gets the AccessibleContext associated with this Label.
public int	Returns: the alignment of this label getAlignment() Gets the current alignment of this label.
public String	Returns: the text of this label, or `null` if the text has been set to `null`. getText() Gets the text of this label.
private static native void	initIDs() Hides java.awt.Component.initIDs. Initialize JNI field and method IDs
protected String	Returns: the parameter string of this label paramString() Overrides java.awt.Component.paramString. Returns a string representing the state of this `Label`.
private void	readObject(ObjectInputStream the `ObjectInputStream` to read s) Hides java.awt.Component.readObject. Read a label from an object input stream.
public synchronized void	setAlignment(int the alignment to be set. alignment) Sets the alignment for this label to the specified alignment.
public void	setText(String the text that this label displays. If `text` is `null`, it is treated for display purposes like an empty string `""`. text) Sets the text for this label to the specified text.

Inherited from java.awt.Component:: action add addComponentListener addFocusListener addHierarchyBoundsListener addHierarchyListener addInputMethodListener addKeyListener addMouseListener addMouseMotionListener addMouseWheelListener addPropertyChangeListener addPropertyChangeListener adjustListeningChildrenOnParent applyComponentOrientation applyCompoundShape applyCurrentShape areBoundsValid areFocusTraversalKeysSet areInputMethodsEnabled autoProcessMouseWheel bounds canBeFocusOwner canBeFocusOwnerRecursively checkGD checkImage checkImage checkTreeLock clearCurrentFocusCycleRootOnHide clearMostRecentFocusOwnerOnHide coalesceEvents contains contains containsFocus countHierarchyMembers createBufferStrategy createBufferStrategy createHierarchyEvents createImage createImage createVolatileImage createVolatileImage deliverEvent disable disableEvents dispatchEvent dispatchEventImpl dispatchMouseWheelToAncestor doLayout enable enable enableEvents enableInputMethods eventEnabled eventTypeEnabled findUnderMouseInWindow firePropertyChange firePropertyChange firePropertyChange firePropertyChange firePropertyChange firePropertyChange firePropertyChange firePropertyChange firePropertyChange getAccessibleIndexInParent getAccessibleStateSet getAlignmentX getAlignmentY getBackBuffer getBackground getBaseline getBaselineResizeBehavior getBounds getBounds getBoundsOp getBufferStrategy getColorModel getComponentAt getComponentAt getComponentFactory getComponentListeners getComponentOrientation getContainer getContainingWindow getCursor getCursor_NoClientCode getDropTarget getFocusCycleRootAncestor getFocusListeners getFocusTraversalKeys getFocusTraversalKeys_NoIDCheck getFocusTraversalKeysEnabled getFont getFont_NoClientCode getFontMetrics getForeground getGraphics getGraphics_NoClientCode getGraphicsConfiguration getGraphicsConfiguration_NoClientCode getHeight getHierarchyBoundsListeners getHierarchyListeners getHWPeerAboveMe getIgnoreRepaint getInputContext getInputMethodListeners getInputMethodRequests getKeyListeners getListeners getLocale getLocation getLocation getLocationOnScreen getLocationOnScreen_NoTreeLock getLocationOnWindow getMaximumSize getMinimumSize getMouseListeners getMouseMotionListeners getMousePosition getMouseWheelListeners getName getNativeContainer getNextFocusCandidate getNormalShape getObjectLock getOpaqueShape getParent getParent_NoClientCode getPreferredSize getPropertyChangeListeners getPropertyChangeListeners getSiblingIndexAbove getSiblingIndexBelow getSize getSize getToolkit getToolkitImpl getTraversalRoot getTreeLock getWidth getX getY gotFocus handleEvent hasFocus hide imageUpdate initializeFocusTraversalKeys inside invalidate invalidateIfValid invalidateParent isAutoFocusTransferOnDisposal isBackgroundSet isCoalescingEnabled isCursorSet isDisplayable isDoubleBuffered isEnabled isEnabledImpl isFocusable isFocusCycleRoot isFocusOwner isFocusTraversable isFocusTraversableOverridden isFontSet isForegroundSet isInstanceOf isLightweight isMaximumSizeSet isMinimumSizeSet isMixingNeeded isNonOpaqueForMixing isOpaque isPreferredSizeSet isRecursivelyVisible isSameOrAncestorOf isShowing isValid isVisible isVisible_NoClientCode keyDown keyUp layout lightweightPaint lightweightPrint list list list list list locate location lostFocus minimumSize mixOnHiding mixOnReshaping mixOnShowing mixOnValidating mixOnZOrderChanging mouseDown mouseDrag mouseEnter mouseExit mouseMove mouseUp move nextFocus numListening paint paintAll paintHeavyweightComponents pointRelativeToComponent postEvent postsOldMouseEvents preferredSize prepareImage prepareImage print printAll printHeavyweightComponents processComponentEvent processEvent processFocusEvent processHierarchyBoundsEvent processHierarchyEvent processInputMethodEvent processKeyEvent processMouseEvent processMouseMotionEvent processMouseWheelEvent relocateComponent remove removeComponentListener removeFocusListener removeHierarchyBoundsListener removeHierarchyListener removeInputMethodListener removeKeyListener removeMouseListener removeMouseMotionListener removeMouseWheelListener removeNotify removePropertyChangeListener removePropertyChangeListener repaint repaint repaint repaint requestFocus requestFocus requestFocus requestFocus requestFocusHelper requestFocusHelper requestFocusInWindow requestFocusInWindow requestFocusInWindow requestFocusInWindow reshape resize resize revalidate revalidateSynchronously setAutoFocusTransferOnDisposal setBackground setBounds setBounds setBoundsOp setComponentOrientation setCursor setDropTarget setEnabled setFocusable setFocusTraversalKeys setFocusTraversalKeys_NoIDCheck setFocusTraversalKeysEnabled setFont setForeground setGraphicsConfiguration setIgnoreRepaint setLocale setLocation setLocation setMaximumSize setMinimumSize setMixingCutoutShape setName setPreferredSize setRequestFocusController setSize setSize setVisible show show size subtractAndApplyShape subtractAndApplyShapeBelowMe toString transferFocus transferFocus transferFocusBackward transferFocusBackward transferFocusUpCycle update updateChildGraphicsData updateCursorImmediately updateGraphicsData updateZOrder validate

Field Detail

alignment back to summary

alignment	back to summary
pack-priv int alignment The label's alignment. The default alignment is set to be left justified. See Also `getAlignment()`, `setAlignment(int)`

pack-priv int alignment

The label's alignment. The default alignment is set to be left justified.

See Also: getAlignment(), setAlignment(int)

base	back to summary
private static final String base

CENTER	back to summary
public static final int CENTER Indicates that the label should be centered.

LEFT	back to summary
public static final int LEFT Indicates that the label should be left justified.

nameCounter	back to summary
private static int nameCounter

RIGHT	back to summary
public static final int RIGHT Indicates that the label should be right justified.

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

serialVersionUID

back to summary

private static final long serialVersionUID

Hides java.awt.Component.serialVersionUID.

Use serialVersionUID from JDK 1.1 for interoperability.

Annotations

@Serial

text back to summary

text	back to summary
pack-priv String text The text of this label. This text can be modified by the program but never by the user. See Also `getText()`, `setText(String)`

pack-priv String text

The text of this label. This text can be modified by the program but never by the user.

See Also: getText(), setText(String)

Constructor Detail

Label back to summary

Label	back to summary
public Label() throws HeadlessException Constructs an empty label. The text of the label is the empty string `""`. Exceptions HeadlessException: if GraphicsEnvironment.isHeadless() returns true. See Also `java.awt.GraphicsEnvironment#isHeadless`

public Label() throws HeadlessException

Constructs an empty label. The text of the label is the empty string "".

Exceptions

HeadlessException:: if GraphicsEnvironment.isHeadless() returns true.

Label back to summary

Label	back to summary
public Label(String text) throws HeadlessException Constructs a new label with the specified string of text, left justified. Parameters text:String the string that the label presents. A `null` value will be accepted without causing a NullPointerException to be thrown. Exceptions HeadlessException: if GraphicsEnvironment.isHeadless() returns true. See Also `java.awt.GraphicsEnvironment#isHeadless`

public Label(String text) throws HeadlessException

Constructs a new label with the specified string of text, left justified.

Parameters

text:String: the string that the label presents. A null value will be accepted without causing a NullPointerException to be thrown.

Exceptions

HeadlessException:: if GraphicsEnvironment.isHeadless() returns true.

Label back to summary

Label	back to summary
public Label(String text, int alignment) throws HeadlessException Constructs a new label that presents the specified string of text with the specified alignment. Possible values for `alignment` are `Label.LEFT`, `Label.RIGHT`, and `Label.CENTER`. Parameters text:String the string that the label presents. A `null` value will be accepted without causing a NullPointerException to be thrown. alignment:int the alignment value. Exceptions HeadlessException: if GraphicsEnvironment.isHeadless() returns true. See Also `java.awt.GraphicsEnvironment#isHeadless`

public Label(String text, int alignment) throws HeadlessException

Constructs a new label that presents the specified string of text with the specified alignment. Possible values for alignment are Label.LEFT, Label.RIGHT, and Label.CENTER.

Parameters

text:String: the string that the label presents. A null value will be accepted without causing a NullPointerException to be thrown.
alignment:int: the alignment value.

Exceptions

HeadlessException:: if GraphicsEnvironment.isHeadless() returns true.

Method Detail

addNotify	back to summary
public void addNotify() Overrides java.awt.Component.addNotify. Creates the peer for this label. The peer allows us to modify the appearance of the label without changing its functionality.

addNotify

back to summary

public void addNotify()

Overrides java.awt.Component.addNotify.

Creates the peer for this label. The peer allows us to modify the appearance of the label without changing its functionality.

constructComponentName back to summary

constructComponentName	back to summary
pack-priv String constructComponentName() Overrides java.awt.Component.constructComponentName. Construct a name for this component. Called by getName() when the name is `null`.

pack-priv String constructComponentName()

Overrides java.awt.Component.constructComponentName.

Construct a name for this component. Called by getName() when the name is null.

getAccessibleContext	back to summary
public AccessibleContext getAccessibleContext() Overrides java.awt.Component.getAccessibleContext. Implements javax.accessibility.Accessible.getAccessibleContext. Gets the AccessibleContext associated with this Label. For labels, the AccessibleContext takes the form of an AccessibleAWTLabel. A new AccessibleAWTLabel instance is created if necessary. Returns:AccessibleContext an AccessibleAWTLabel that serves as the AccessibleContext of this Label Since 1.3

getAccessibleContext

back to summary

public AccessibleContext getAccessibleContext()

Overrides java.awt.Component.getAccessibleContext.

Implements javax.accessibility.Accessible.getAccessibleContext.

Gets the AccessibleContext associated with this Label. For labels, the AccessibleContext takes the form of an AccessibleAWTLabel. A new AccessibleAWTLabel instance is created if necessary.

Returns:AccessibleContext: an AccessibleAWTLabel that serves as the AccessibleContext of this Label
Since: 1.3

getAlignment back to summary

getAlignment	back to summary
public int getAlignment() Gets the current alignment of this label. Possible values are `Label.LEFT`, `Label.RIGHT`, and `Label.CENTER`. Returns:int the alignment of this label See Also `java.awt.Label#setAlignment`

public int getAlignment()

Gets the current alignment of this label. Possible values are Label.LEFT, Label.RIGHT, and Label.CENTER.

Returns:int: the alignment of this label
See Also: java.awt.Label#setAlignment

getText back to summary

getText	back to summary
public String getText() Gets the text of this label. Returns:String the text of this label, or `null` if the text has been set to `null`. See Also `java.awt.Label#setText`

public String getText()

Gets the text of this label.

Returns:String: the text of this label, or null if the text has been set to null.
See Also: java.awt.Label#setText

initIDs	back to summary
private static native void initIDs() Hides java.awt.Component.initIDs. Initialize JNI field and method IDs

initIDs

back to summary

private static native void initIDs()

Hides java.awt.Component.initIDs.

Initialize JNI field and method IDs

paramString back to summary

paramString	back to summary
protected String paramString() Overrides java.awt.Component.paramString. Returns a string representing the state of this `Label`. 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:String the parameter string of this label

protected String paramString()

Overrides java.awt.Component.paramString.

Returns a string representing the state of this Label. 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:String: the parameter string of this label

readObject back to summary

readObject	back to summary
private void readObject(ObjectInputStream s) throws ClassNotFoundException, IOException, HeadlessException Hides java.awt.Component.readObject. Read a label from an object input stream. Parameters s:ObjectInputStream the `ObjectInputStream` to read Annotations @Serial Exceptions ClassNotFoundException: if the class of a serialized object could not be found IOException: if an I/O error occurs HeadlessException: if `GraphicsEnvironment.isHeadless()` returns `true` Since 1.4 See Also `java.awt.GraphicsEnvironment#isHeadless`

private void readObject(ObjectInputStream s) throws ClassNotFoundException, IOException, HeadlessException

Hides java.awt.Component.readObject.

Read a label from an object input stream.

Parameters

s:ObjectInputStream: the ObjectInputStream to read

Annotations

@Serial

Exceptions

ClassNotFoundException:: if the class of a serialized object could not be found
IOException:: if an I/O error occurs
HeadlessException:: if GraphicsEnvironment.isHeadless() returns true

Since

1.4

setAlignment back to summary

setAlignment	back to summary
public synchronized void setAlignment(int alignment) Sets the alignment for this label to the specified alignment. Possible values are `Label.LEFT`, `Label.RIGHT`, and `Label.CENTER`. Parameters alignment:int the alignment to be set. Exceptions IllegalArgumentException: if an improper value for `alignment` is given. See Also `java.awt.Label#getAlignment`

public synchronized void setAlignment(int alignment)

Sets the alignment for this label to the specified alignment. Possible values are Label.LEFT, Label.RIGHT, and Label.CENTER.

Parameters

alignment:int: the alignment to be set.

Exceptions

IllegalArgumentException:: if an improper value for alignment is given.

See Also

java.awt.Label#getAlignment

setText back to summary

setText	back to summary
public void setText(String text) Sets the text for this label to the specified text. Parameters text:String the text that this label displays. If `text` is `null`, it is treated for display purposes like an empty string `""`. See Also `java.awt.Label#getText`

public void setText(String text)

Sets the text for this label to the specified text.

Parameters

text:String: the text that this label displays. If text is null, it is treated for display purposes like an empty string "".

See Also

java.awt.Label#getText

java.awt back to summary

protected Class Label.AccessibleAWTLabel

Class Inheritance

extends AccessibleAWTComponent

java.lang.Object
javax.accessibility.AccessibleContext
java.awt.Component.AccessibleAWTComponent
java.awt.Label.AccessibleAWTLabel

This class implements accessibility support for the Label class. It provides an implementation of the Java Accessibility API appropriate to label user-interface elements.

Since: 1.3

Field Summary

Modifier and Type	Field and Description
private static final long	serialVersionUID Hides java.awt.Component.AccessibleAWTComponent.serialVersionUID. Use serialVersionUID from JDK 1.3 for interoperability.

Inherited from java.awt.Component.AccessibleAWTComponent:: accessibleAWTComponentHandler accessibleAWTFocusHandler

Constructor Summary

Access	Constructor and Description
public	AccessibleAWTLabel() Constructor for the accessible label.

Method Summary

Modifier and Type	Method and Description
public String	Returns: the localized name of the object -- can be null if this object does not have a name getAccessibleName() Overrides java.awt.Component.AccessibleAWTComponent.getAccessibleName. Get the accessible name of this object.
public AccessibleRole	Returns: an instance of AccessibleRole describing the role of the object getAccessibleRole() Overrides java.awt.Component.AccessibleAWTComponent.getAccessibleRole. Get the role of this object.

Field Detail

serialVersionUID	back to summary
private static final long serialVersionUID Hides java.awt.Component.AccessibleAWTComponent.serialVersionUID. Use serialVersionUID from JDK 1.3 for interoperability. Annotations @Serial

serialVersionUID

back to summary

private static final long serialVersionUID

Hides java.awt.Component.AccessibleAWTComponent.serialVersionUID.

Use serialVersionUID from JDK 1.3 for interoperability.

Annotations

@Serial

Constructor Detail

AccessibleAWTLabel	back to summary
public AccessibleAWTLabel() Constructor for the accessible label.

Method Detail

getAccessibleName back to summary

getAccessibleName	back to summary
public String getAccessibleName() Overrides java.awt.Component.AccessibleAWTComponent.getAccessibleName. Get the accessible name of this object. Returns:String the localized name of the object -- can be null if this object does not have a name See Also `AccessibleContext#setAccessibleName`

public String getAccessibleName()

Overrides java.awt.Component.AccessibleAWTComponent.getAccessibleName.

Get the accessible name of this object.

Returns:String: the localized name of the object -- can be null if this object does not have a name
See Also: AccessibleContext#setAccessibleName

getAccessibleRole back to summary

getAccessibleRole	back to summary
public AccessibleRole getAccessibleRole() Overrides java.awt.Component.AccessibleAWTComponent.getAccessibleRole. Get the role of this object. Returns:AccessibleRole an instance of AccessibleRole describing the role of the object See Also `AccessibleRole`

public AccessibleRole getAccessibleRole()

Overrides java.awt.Component.AccessibleAWTComponent.getAccessibleRole.

Get the role of this object.

Returns:AccessibleRole: an instance of AccessibleRole describing the role of the object
See Also: AccessibleRole