Java java.awt Class TextArea（JDK8）

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Java™ Platform
Standard Ed. 8

All Classes

Summary:
Nested |
Field |
Constr |
Method

Detail:
Field |
Constr |
Method

java.lang.Object
- java.awt.Component
- - java.awt.TextComponent
  - - java.awt.TextArea

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible
```
public class TextArea
extends TextComponent
```
A TextArea object is a multi-line region that displays text. It can be set to allow editing or to be read-only.
The following image shows the appearance of a text area:

This text area could be created by the following line of code:
```
 new TextArea("Hello", 5, 40);
 
```
Since:

JDK1.0

See Also:

Serialized Form

Nested Class Summary

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

Nested classes/interfaces inherited from class java.awt.TextComponent
TextComponent.AccessibleAWTTextComponent

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`	`SCROLLBARS_BOTH` Create and display both vertical and horizontal scrollbars.
`static int`	`SCROLLBARS_HORIZONTAL_ONLY` Create and display horizontal scrollbar only.
`static int`	`SCROLLBARS_NONE` Do not create or display any scrollbars for the text area.
`static int`	`SCROLLBARS_VERTICAL_ONLY` Create and display vertical scrollbar only.

Fields inherited from class java.awt.TextComponent
textListener

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
`TextArea()` Constructs a new text area with the empty string as text.
`TextArea(int rows, int columns)` Constructs a new text area with the specified number of rows and columns and the empty string as text.
`TextArea(String text)` Constructs a new text area with the specified text.
`TextArea(String text, int rows, int columns)` Constructs a new text area with the specified text, and with the specified number of rows and columns.
`TextArea(String text, int rows, int columns, int scrollbars)` Constructs a new text area with the specified text, and with the rows, columns, and scroll bar visibility as specified.

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`void`	`addNotify()` Creates the `TextArea`'s peer.
`void`	`append(String str)` Appends the given text to the text area's current text.
`void`	`appendText(String str)` Deprecated. As of JDK version 1.1, replaced by `append(String)`.
`AccessibleContext`	`getAccessibleContext()` Returns the `AccessibleContext` associated with this `TextArea`.
`int`	`getColumns()` Returns the number of columns in this text area.
`Dimension`	`getMinimumSize()` Determines the minimum size of this text area.
`Dimension`	`getMinimumSize(int rows, int columns)` Determines the minimum size of a text area with the specified number of rows and columns.
`Dimension`	`getPreferredSize()` Determines the preferred size of this text area.
`Dimension`	`getPreferredSize(int rows, int columns)` Determines the preferred size of a text area with the specified number of rows and columns.
`int`	`getRows()` Returns the number of rows in the text area.
`int`	`getScrollbarVisibility()` Returns an enumerated value that indicates which scroll bars the text area uses.
`void`	`insert(String str, int pos)` Inserts the specified text at the specified position in this text area.
`void`	`insertText(String str, int pos)` Deprecated. As of JDK version 1.1, replaced by `insert(String, int)`.
`Dimension`	`minimumSize()` Deprecated. As of JDK version 1.1, replaced by `getMinimumSize()`.
`Dimension`	`minimumSize(int rows, int columns)` Deprecated. As of JDK version 1.1, replaced by `getMinimumSize(int, int)`.
`protected String`	`paramString()` Returns a string representing the state of this `TextArea`.
`Dimension`	`preferredSize()` Deprecated. As of JDK version 1.1, replaced by `getPreferredSize()`.
`Dimension`	`preferredSize(int rows, int columns)` Deprecated. As of JDK version 1.1, replaced by `getPreferredSize(int, int)`.
`void`	`replaceRange(String str, int start, int end)` Replaces text between the indicated start and end positions with the specified replacement text.
`void`	`replaceText(String str, int start, int end)` Deprecated. As of JDK version 1.1, replaced by `replaceRange(String, int, int)`.
`void`	`setColumns(int columns)` Sets the number of columns for this text area.
`void`	`setRows(int rows)` Sets the number of rows for this text area.

Methods inherited from class java.awt.TextComponent
addTextListener, enableInputMethods, getBackground, getCaretPosition, getInputMethodRequests, getListeners, getSelectedText, getSelectionEnd, getSelectionStart, getText, getTextListeners, isEditable, processEvent, processTextEvent, removeNotify, removeTextListener, select, selectAll, setBackground, setCaretPosition, setEditable, setSelectionEnd, setSelectionStart, setText

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, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getAlignmentX, getAlignmentY, 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, getKeyListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, 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, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paint, paintAll, postEvent, prepareImage, prepareImage, print, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, 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
  - SCROLLBARS_BOTH
```
public static final int SCROLLBARS_BOTH
```
    Create and display both vertical and horizontal scrollbars.
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Constant Field Values
  - SCROLLBARS_VERTICAL_ONLY
```
public static final int SCROLLBARS_VERTICAL_ONLY
```
    Create and display vertical scrollbar only.
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Constant Field Values
  - SCROLLBARS_HORIZONTAL_ONLY
```
public static final int SCROLLBARS_HORIZONTAL_ONLY
```
    Create and display horizontal scrollbar only.
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Constant Field Values
  - SCROLLBARS_NONE
```
public static final int SCROLLBARS_NONE
```
    Do not create or display any scrollbars for the text area.
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - TextArea
```
public TextArea()
         throws HeadlessException
```
    Constructs a new text area with the empty string as text. This text area is created with scrollbar visibility equal to SCROLLBARS_BOTH, so both vertical and horizontal scrollbars will be visible for this text area.
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless returns true
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
  - TextArea
```
public TextArea(String text)
         throws HeadlessException
```
    Constructs a new text area with the specified text. This text area is created with scrollbar visibility equal to SCROLLBARS_BOTH, so both vertical and horizontal scrollbars will be visible for this text area.
    
    Parameters:
    
    text - the text to be displayed; if text is null, the empty string "" will be displayed
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless returns true
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
  - TextArea
```
public TextArea(int rows,
                int columns)
         throws HeadlessException
```
    Constructs a new text area with the specified number of rows and columns and the empty string as text. A column is an approximate average character width that is platform-dependent. The text area is created with scrollbar visibility equal to SCROLLBARS_BOTH, so both vertical and horizontal scrollbars will be visible for this text area.
    
    Parameters:
    
    rows - the number of rows
    
    columns - the number of columns
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless returns true
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
  - TextArea
```
public TextArea(String text,
                int rows,
                int columns)
         throws HeadlessException
```
    Constructs a new text area with the specified text, and with the specified number of rows and columns. A column is an approximate average character width that is platform-dependent. The text area is created with scrollbar visibility equal to SCROLLBARS_BOTH, so both vertical and horizontal scrollbars will be visible for this text area.
    
    Parameters:
    
    text - the text to be displayed; if text is null, the empty string "" will be displayed
    
    rows - the number of rows
    
    columns - the number of columns
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless returns true
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
  - TextArea
```
public TextArea(String text,
                int rows,
                int columns,
                int scrollbars)
         throws HeadlessException
```
    Constructs a new text area with the specified text, and with the rows, columns, and scroll bar visibility as specified. All TextArea constructors defer to this one.
    The TextArea class defines several constants that can be supplied as values for the scrollbars argument:
    - SCROLLBARS_BOTH,
    - SCROLLBARS_VERTICAL_ONLY,
    - SCROLLBARS_HORIZONTAL_ONLY,
    - SCROLLBARS_NONE.
    Any other value for the scrollbars argument is invalid and will result in this text area being created with scrollbar visibility equal to the default value of SCROLLBARS_BOTH.
    Parameters:
    
    text - the text to be displayed; if text is null, the empty string "" will be displayed
    
    rows - the number of rows; if rows is less than 0, rows is set to 0
    
    columns - the number of columns; if columns is less than 0, columns is set to 0
    
    scrollbars - a constant that determines what scrollbars are created to view the text area
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless returns true
    
    Since:
    
    JDK1.1
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
- Method Detail
  - addNotify
```
public void addNotify()
```
    Creates the TextArea's peer. The peer allows us to modify the appearance of the TextArea without changing any of its functionality.
    
    Overrides:
    
    addNotify in class TextComponent
    
    See Also:
    
    TextComponent.removeNotify()
  - insert
```
public void insert(String str,
                   int pos)
```
    Inserts the specified text at the specified position in this text area.
    Note that passing null or inconsistent parameters is invalid and will result in unspecified behavior.
    
    Parameters:
    
    str - the non-null text to insert
    
    pos - the position at which to insert
    
    Since:
    
    JDK1.1
    
    See Also:
    
    TextComponent.setText(java.lang.String), replaceRange(java.lang.String, int, int), append(java.lang.String)
  - insertText
```
@Deprecated
public void insertText(String str,
                                   int pos)
```
    Deprecated. As of JDK version 1.1, replaced by insert(String, int).
  - append
```
public void append(String str)
```
    Appends the given text to the text area's current text.
    Note that passing null or inconsistent parameters is invalid and will result in unspecified behavior.
    
    Parameters:
    
    str - the non-null text to append
    
    Since:
    
    JDK1.1
    
    See Also:
    
    insert(java.lang.String, int)
  - appendText
```
@Deprecated
public void appendText(String str)
```
    Deprecated. As of JDK version 1.1, replaced by append(String).
  - replaceRange
```
public void replaceRange(String str,
                         int start,
                         int end)
```
    Replaces text between the indicated start and end positions with the specified replacement text. The text at the end position will not be replaced. The text at the start position will be replaced (unless the start position is the same as the end position). The text position is zero-based. The inserted substring may be of a different length than the text it replaces.
    Note that passing null or inconsistent parameters is invalid and will result in unspecified behavior.
    
    Parameters:
    
    str - the non-null text to use as the replacement
    
    start - the start position
    
    end - the end position
    
    Since:
    
    JDK1.1
    
    See Also:
    
    insert(java.lang.String, int)
  - replaceText
```
@Deprecated
public void replaceText(String str,
                                    int start,
                                    int end)
```
    Deprecated. As of JDK version 1.1, replaced by replaceRange(String, int, int).
  - getRows
```
public int getRows()
```
    Returns the number of rows in the text area.
    
    Returns:
    
    the number of rows in the text area
    
    Since:
    
    JDK1
    
    See Also:
    
    setRows(int), getColumns()
  - setRows
```
public void setRows(int rows)
```
    Sets the number of rows for this text area.
    
    Parameters:
    
    rows - the number of rows
    
    Throws:
    
    IllegalArgumentException - if the value supplied for rows is less than 0
    
    Since:
    
    JDK1.1
    
    See Also:
    
    getRows(), setColumns(int)
  - getColumns
```
public int getColumns()
```
    Returns the number of columns in this text area.
    
    Returns:
    
    the number of columns in the text area
    
    See Also:
    
    setColumns(int), getRows()
  - setColumns
```
public void setColumns(int columns)
```
    Sets the number of columns for this text area.
    
    Parameters:
    
    columns - the number of columns
    
    Throws:
    
    IllegalArgumentException - if the value supplied for columns is less than 0
    
    Since:
    
    JDK1.1
    
    See Also:
    
    getColumns(), setRows(int)
  - getScrollbarVisibility
```
public int getScrollbarVisibility()
```
    Returns an enumerated value that indicates which scroll bars the text area uses.
    The TextArea class defines four integer constants that are used to specify which scroll bars are available. TextArea has one constructor that gives the application discretion over scroll bars.
    
    Returns:
    
    an integer that indicates which scroll bars are used
    
    Since:
    
    JDK1.1
    
    See Also:
    
    SCROLLBARS_BOTH, SCROLLBARS_VERTICAL_ONLY, SCROLLBARS_HORIZONTAL_ONLY, SCROLLBARS_NONE, TextArea(java.lang.String, int, int, int)
  - getPreferredSize
```
public Dimension getPreferredSize(int rows,
                                  int columns)
```
    Determines the preferred size of a text area with the specified number of rows and columns.
    
    Parameters:
    
    rows - the number of rows
    
    columns - the number of columns
    
    Returns:
    
    the preferred dimensions required to display the text area with the specified number of rows and columns
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Component.getPreferredSize()
  - preferredSize
```
@Deprecated
public Dimension preferredSize(int rows,
                                           int columns)
```
    Deprecated. As of JDK version 1.1, replaced by getPreferredSize(int, int).
  - getPreferredSize
```
public Dimension getPreferredSize()
```
    Determines the preferred size of this text area.
    
    Overrides:
    
    getPreferredSize in class Component
    
    Returns:
    
    the preferred dimensions needed for this text area
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Component.getPreferredSize()
  - preferredSize
```
@Deprecated
public Dimension preferredSize()
```
    Deprecated. As of JDK version 1.1, replaced by getPreferredSize().
    
    Overrides:
    
    preferredSize in class Component
  - getMinimumSize
```
public Dimension getMinimumSize(int rows,
                                int columns)
```
    Determines the minimum size of a text area with the specified number of rows and columns.
    
    Parameters:
    
    rows - the number of rows
    
    columns - the number of columns
    
    Returns:
    
    the minimum dimensions required to display the text area with the specified number of rows and columns
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Component.getMinimumSize()
  - minimumSize
```
@Deprecated
public Dimension minimumSize(int rows,
                                         int columns)
```
    Deprecated. As of JDK version 1.1, replaced by getMinimumSize(int, int).
  - getMinimumSize
```
public Dimension getMinimumSize()
```
    Determines the minimum size of this text area.
    
    Overrides:
    
    getMinimumSize in class Component
    
    Returns:
    
    the preferred dimensions needed for this text area
    
    Since:
    
    JDK1.1
    
    See Also:
    
    Component.getPreferredSize()
  - minimumSize
```
@Deprecated
public Dimension minimumSize()
```
    Deprecated. As of JDK version 1.1, replaced by getMinimumSize().
    
    Overrides:
    
    minimumSize in class Component
  - paramString
```
protected String paramString()
```
    Returns a string representing the state of this TextArea. 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 TextComponent
    
    Returns:
    
    the parameter string of this text area
  - getAccessibleContext
```
public AccessibleContext getAccessibleContext()
```
    Returns the AccessibleContext associated with this TextArea. For text areas, the AccessibleContext takes the form of an AccessibleAWTTextArea. A new AccessibleAWTTextArea instance is created if necessary.
    
    Specified by:
    
    getAccessibleContext in interface Accessible
    
    Overrides:
    
    getAccessibleContext in class TextComponent
    
    Returns:
    
    an AccessibleAWTTextArea that serves as the AccessibleContext of this TextArea
    
    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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Constr |
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Java java.awt Class TextArea（JDK8）

Class TextArea

Nested Class Summary

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

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

Field Summary

Fields inherited from class java.awt.TextComponent

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.TextComponent

Methods inherited from class java.awt.Component

Methods inherited from class java.lang.Object

Field Detail

SCROLLBARS_BOTH

SCROLLBARS_VERTICAL_ONLY

SCROLLBARS_HORIZONTAL_ONLY

SCROLLBARS_NONE

Constructor Detail

TextArea

TextArea

TextArea

TextArea

TextArea

Method Detail

addNotify

insert

insertText

append

appendText

replaceRange

replaceText

getRows

setRows

getColumns

setColumns

getScrollbarVisibility

getPreferredSize

preferredSize

getPreferredSize

preferredSize

getMinimumSize

minimumSize

getMinimumSize

minimumSize

paramString

getAccessibleContext