Class TextArea

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:

A TextArea showing the word 'Hello!'

This text area could be created by the following line of code:

new TextArea("Hello", 5, 40);

Since:: 1.0
See Also:: Serialized Form

Nested Class Summary

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

Nested classes/interfaces declared in class java.awt.TextComponent

TextComponent.AccessibleAWTTextComponent

Nested classes/interfaces declared in class java.awt.Component

Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields
Modifier and Type	Field	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 declared in class java.awt.TextComponent

textListener

Fields declared in class java.awt.Component

accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields declared in interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Constructors
Constructor	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	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 declared in class java.awt.TextComponent

addTextListener, enableInputMethods, getBackground, getCaretPosition, getListeners, getSelectedText, getSelectionEnd, getSelectionStart, getText, getTextListeners, isEditable, processEvent, processTextEvent, removeNotify, removeTextListener, select, selectAll, setBackground, setCaretPosition, setEditable, setSelectionEnd, setSelectionStart, setText

Methods declared in 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, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, 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, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setMixingCutoutShape, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle, update, validate

Methods declared in 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:: 1.1
See Also:: Constant Field Values

SCROLLBARS_VERTICAL_ONLY

public static final int SCROLLBARS_VERTICAL_ONLY

Create and display vertical scrollbar only.

Since:: 1.1
See Also:: Constant Field Values

SCROLLBARS_HORIZONTAL_ONLY

public static final int SCROLLBARS_HORIZONTAL_ONLY

Create and display horizontal scrollbar only.

Since:: 1.1
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:: 1.1
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:: 1.1
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:: 1.1
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).

Inserts the specified text at the specified position in this text area.

Parameters:: str - the non-null text to insert; pos - the position at which to insert

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:: 1.1
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).

Appends the given text to the text area's current text.

Parameters:: str - the text to append

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:: 1.1
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).

Replaces a range of characters between the indicated start and end positions with the specified replacement text (the text at the end position will not be replaced).

Parameters:: str - the non-null text to use as the replacement; start - the start position; end - the end position

getRows

public int getRows()

Returns the number of rows in the text area.

Returns:: the number of rows in the text area
Since:: 1.0
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:: 1.1
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:: 1.1
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:: 1.1
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:: 1.1
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).

Determines the preferred size of the 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 needed for the text area

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:: 1.1
See Also:: Component.getPreferredSize()

preferredSize

@Deprecated
public Dimension preferredSize()

Deprecated.

As of JDK version 1.1, replaced by getPreferredSize().

Description copied from class: Component

Returns the component's preferred size.

Overrides:: preferredSize in class Component
Returns:: the component's preferred size

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:: 1.1
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).

Determines the minimum size of the text area with the specified number of rows and columns.

Parameters:: rows - the number of rows; columns - the number of columns
Returns:: the minimum size for the text area

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:: 1.1
See Also:: Component.getPreferredSize()

minimumSize

@Deprecated
public Dimension minimumSize()

Deprecated.

As of JDK version 1.1, replaced by getMinimumSize().

Description copied from class: Component

Returns the minimum size of this component.

Overrides:: minimumSize in class Component
Returns:: the minimum size of this 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