Java java.awt Class Label（JDK8）

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Java™ Platform
Standard Ed. 8

All Classes

Summary:
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Field |
Constr |
Method

Detail:
Field |
Constr |
Method

java.lang.Object
- java.awt.Component
- - java.awt.Label

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible
```
public class Label
extends Component
implements Accessible
```
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:
Since:

JDK1.0

See Also:

Serialized Form

Nested Class Summary

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

Nested classes/interfaces inherited from class java.awt.Component
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`CENTER` Indicates that the label should be centered.
`static int`	`LEFT` Indicates that the label should be left justified.
`static int`	`RIGHT` Indicates that the label should be right justified.

Fields inherited from class java.awt.Component
accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Constructors
Constructor and Description
`Label()` Constructs an empty label.
`Label(String text)` Constructs a new label with the specified string of text, left justified.
`Label(String text, int alignment)` Constructs a new label that presents the specified string of text with the specified alignment.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addNotify()` Creates the peer for this label.
`AccessibleContext`	`getAccessibleContext()` Gets the AccessibleContext associated with this Label.
`int`	`getAlignment()` Gets the current alignment of this label.
`String`	`getText()` Gets the text of this label.
`protected String`	`paramString()` Returns a string representing the state of this `Label`.
`void`	`setAlignment(int alignment)` Sets the alignment for this label to the specified alignment.
`void`	`setText(String text)` Sets the text for this label to the specified text.

Methods inherited from class java.awt.Component
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getAlignmentX, getAlignmentY, getBackground, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeys, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPreferredSize, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusCycleRoot, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, layout, list, list, list, list, list, locate, location, lostFocus, minimumSize, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paint, paintAll, postEvent, preferredSize, prepareImage, prepareImage, print, printAll, processComponentEvent, processEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle, update, validate

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - LEFT
```
public static final int LEFT
```
    Indicates that the label should be left justified.
    
    See Also:
    
    Constant Field Values
  - CENTER
```
public static final int CENTER
```
    Indicates that the label should be centered.
    
    See Also:
    
    Constant Field Values
  - RIGHT
```
public static final int RIGHT
```
    Indicates that the label should be right justified.
    
    Since:
    
    JDK1.0t.
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - Label
```
public Label()
      throws HeadlessException
```
    Constructs an empty label. The text of the label is the empty string "".
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
  - Label
```
public Label(String text)
      throws HeadlessException
```
    Constructs a new label with the specified string of text, left justified.
    
    Parameters:
    
    text - the string that the label presents. A null value will be accepted without causing a NullPointerException to be thrown.
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
  - Label
```
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 - the string that the label presents. A null value will be accepted without causing a NullPointerException to be thrown.
    
    alignment - the alignment value.
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
- Method Detail
  - addNotify
```
public void addNotify()
```
    Creates the peer for this label. The peer allows us to modify the appearance of the label without changing its functionality.
    
    Overrides:
    
    addNotify in class Component
    
    See Also:
    
    Component.isDisplayable(), Component.removeNotify(), Component.invalidate()
  - getAlignment
```
public int getAlignment()
```
    Gets the current alignment of this label. Possible values are Label.LEFT, Label.RIGHT, and Label.CENTER.
    
    See Also:
    
    setAlignment(int)
  - setAlignment
```
public 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 - the alignment to be set.
    
    Throws:
    
    IllegalArgumentException - if an improper value for alignment is given.
    
    See Also:
    
    getAlignment()
  - getText
```
public String getText()
```
    Gets the text of this label.
    
    Returns:
    
    the text of this label, or null if the text has been set to null.
    
    See Also:
    
    setText(java.lang.String)
  - setText
```
public void setText(String text)
```
    Sets the text for this label to the specified text.
    
    Parameters:
    
    text - the text that this label displays. If text is null, it is treated for display purposes like an empty string "".
    
    See Also:
    
    getText()
  - paramString
```
protected String 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.
    
    Overrides:
    
    paramString in class Component
    
    Returns:
    
    the parameter string of this label
  - getAccessibleContext
```
public AccessibleContext 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.
    
    Specified by:
    
    getAccessibleContext in interface Accessible
    
    Overrides:
    
    getAccessibleContext in class Component
    
    Returns:
    
    an AccessibleAWTLabel that serves as the AccessibleContext of this Label
    
    Since:
    
    1.3

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Java™ Platform
Standard Ed. 8

All Classes

Summary:
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Field |
Constr |
Method

Detail:
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Java java.awt Class Label（JDK8）

Class Label

Nested Class Summary

Nested classes/interfaces inherited from class java.awt.Component

Field Summary

Fields inherited from class java.awt.Component

Fields inherited from interface java.awt.image.ImageObserver

Constructor Summary

Method Summary

Methods inherited from class java.awt.Component

Methods inherited from class java.lang.Object

Field Detail

LEFT

CENTER

RIGHT

Constructor Detail

Label

Label

Label

Method Detail

addNotify

getAlignment

setAlignment

getText

setText

paramString

getAccessibleContext