java.awt
Class TextArea

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

All Implemented Interfaces:

Accessible, ImageObserver, MenuContainer, Serializable

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

Inner Class Summary

protected class

TextArea.AccessibleAWTTextArea This class implements accessibility support for the TextArea class.

Inner classes inherited from class java.awt.TextComponent

TextComponent.AccessibleAWTTextComponent

Inner classes inherited from class java.awt.Component

Component.AccessibleAWTComponent

Field Summary

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

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

TextArea()
Constructs a new text area.

TextArea(int rows, int columns)
Constructs a new empty text area with the specified number of rows and columns.

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

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() Gets the AccessibleContext associated with this TextArea.
int	getColumns() Gets 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() Gets the number of rows in the text area.
int	getScrollbarVisibility() Gets 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 the parameter string representing the state of this text area.
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, getBackground, getCaretPosition, getListeners, getSelectedText, getSelectionEnd, getSelectionStart, getText, 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, addPropertyChangeListener, addPropertyChangeListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, getAlignmentX, getAlignmentY, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getInputContext, getInputMethodRequests, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getName, getParent, getPeer, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isDisplayable, isDoubleBuffered, isEnabled, isFocusTraversable, isLightweight, isOpaque, 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, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, reshape, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFont, setForeground, setLocale, setLocation, setLocation, setName, setSize, setSize, setVisible, show, show, size, toString, transferFocus, 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

SCROLLBARS_VERTICAL_ONLY

public static final int SCROLLBARS_VERTICAL_ONLY

Create and display vertical scrollbar only.

Since:

JDK1.1

SCROLLBARS_HORIZONTAL_ONLY

public static final int SCROLLBARS_HORIZONTAL_ONLY

Create and display horizontal scrollbar only.

Since:

JDK1.1

SCROLLBARS_NONE

public static final int SCROLLBARS_NONE

Do not create or display any scrollbars for the text area.

Since:

JDK1.1

Constructor Detail

TextArea

public TextArea()

Constructs a new text area. 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.

TextArea

public TextArea(String text)

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.

TextArea

public TextArea(int rows,
                int columns)

Constructs a new empty text area 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:

rows - the number of rows

columns - the number of columns

TextArea

public 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. 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.

rows - the number of rows.

columns - the number of columns.

TextArea

public 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.

The TextArea class defines several constants that can be supplied as values for the scrollbars argument: SCROLLBARS_BOTH, SCROLLBARS_VERTICAL_ONLY, SCROLLBARS_HORIZONTAL_ONLY, and 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.

Since:

JDK1.1

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 Component

Following copied from class: java.awt.Component

See Also:

Component.isDisplayable(), Component.removeNotify()

insert

public void insert(String str,
                   int pos)

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

Parameters:

str - the 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

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.

Parameters:

str - the text to append.

See Also:

insert(java.lang.String, int)

appendText

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.

Parameters:

str - the 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

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()

Gets 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()

Gets 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()

Gets 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.

cols - 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

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

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.

cols - 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

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

public Dimension minimumSize()

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

Overrides:

minimumSize in class Component

paramString

protected String paramString()

Returns the parameter string representing the state of this text area. This string is useful for debugging.

Overrides:

paramString in class TextComponent

Returns:

the parameter string of this text area.

getAccessibleContext

public AccessibleContext getAccessibleContext()

Gets 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.

Overrides:

getAccessibleContext in class TextComponent

Returns:

an AccessibleAWTTextArea that serves as the AccessibleContext of this TextArea