public class JTextField extends JTextComponent implements SwingConstants
JTextField is a lightweight component that allows the editing
 of a single line of text.
 For information on and examples of using text fields,
 see
 How to Use Text Fields
 in The Java Tutorial.
 
 JTextField is intended to be source-compatible
 with java.awt.TextField where it is reasonable to do so.  This
 component has capabilities not found in the java.awt.TextField
 class.  The superclass should be consulted for additional capabilities.
 
 JTextField has a method to establish the string used as the
 command string for the action event that gets fired.  The
 java.awt.TextField used the text of the field as the command
 string for the ActionEvent.
 JTextField will use the command
 string set with the setActionCommand method if not null,
 otherwise it will use the text of the field as a compatibility with
 java.awt.TextField.
 
 The method setEchoChar and getEchoChar
 are not provided directly to avoid a new implementation of a
 pluggable look-and-feel inadvertently exposing password characters.
 To provide password-like services a separate class JPasswordField
 extends JTextField to provide this service with an independently
 pluggable look-and-feel.
 
 The java.awt.TextField could be monitored for changes by adding
 a TextListener for TextEvent's.
 In the JTextComponent based
 components, changes are broadcasted from the model via a
 DocumentEvent to DocumentListeners.
 The DocumentEvent gives
 the location of the change and the kind of change if desired.
 The code fragment might look something like:
 
     DocumentListener myListener = ??;
     JTextField myArea = ??;
     myArea.getDocument().addDocumentListener(myListener);
 
 The horizontal alignment of JTextField can be set to be left
 justified, leading justified, centered, right justified or trailing justified.
 Right/trailing justification is useful if the required size
 of the field text is smaller than the size allocated to it.
 This is determined by the setHorizontalAlignment
 and getHorizontalAlignment methods.  The default
 is to be leading justified.
 
How the text field consumes VK_ENTER events depends on whether the text field has any action listeners. If so, then VK_ENTER results in the listeners getting an ActionEvent, and the VK_ENTER event is consumed. This is compatible with how AWT text fields handle VK_ENTER events. If the text field has no action listeners, then as of v 1.3 the VK_ENTER event is not consumed. Instead, the bindings of ancestor components are processed, which enables the default button feature of JFC/Swing to work.
Customized fields can easily be created by extending the model and changing the default model provided. For example, the following piece of code will create a field that holds only upper case characters. It will work even if text is pasted into from the clipboard or it is altered via programmatic changes.
 public class UpperCaseField extends JTextField {
 
     public UpperCaseField(int cols) {
         super(cols);
     }
 
     protected Document createDefaultModel() {
         return new UpperCaseDocument();
     }
 
     static class UpperCaseDocument extends PlainDocument {
 
         public void insertString(int offs, String str, AttributeSet a)
             throws BadLocationException {
 
             if (str == null) {
                 return;
             }
             char[] upper = str.toCharArray();
             for (int i = 0; i < upper.length; i++) {
                 upper[i] = Character.toUpperCase(upper[i]);
             }
             super.insertString(offs, new String(upper), a);
         }
     }
 }
 Warning: Swing is not thread safe. For more information see Swing's Threading Policy.
 Warning:
 Serialized objects of this class will not be compatible with
 future Swing releases. The current serialization support is
 appropriate for short term storage or RMI between applications running
 the same version of Swing.  As of 1.4, support for long term storage
 of all JavaBeansTM
 has been added to the java.beans package.
 Please see XMLEncoder.
| Modifier and Type | Class and Description | 
|---|---|
| protected class  | JTextField.AccessibleJTextFieldThis class implements accessibility support for the
  JTextFieldclass. | 
JTextComponent.AccessibleJTextComponent, JTextComponent.DropLocation, JTextComponent.KeyBindingJComponent.AccessibleJComponentContainer.AccessibleAWTContainerComponent.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy| Modifier and Type | Field and Description | 
|---|---|
| static String | notifyActionName of the action to send notification that the
 contents of the field have been accepted. | 
DEFAULT_KEYMAP, FOCUS_ACCELERATOR_KEYaccessibleContext, listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOWBOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENTBOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WESTABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH| Constructor and Description | 
|---|
| JTextField()Constructs a new  TextField. | 
| JTextField(Document doc,
          String text,
          int columns)Constructs a new  JTextFieldthat uses the given text
 storage model and the given number of columns. | 
| JTextField(int columns)Constructs a new empty  TextFieldwith the specified
 number of columns. | 
| JTextField(String text)Constructs a new  TextFieldinitialized with the
 specified text. | 
| JTextField(String text,
          int columns)Constructs a new  TextFieldinitialized with the
 specified text and columns. | 
| Modifier and Type | Method and Description | 
|---|---|
| protected void | actionPropertyChanged(Action action,
                     String propertyName)Updates the textfield's state in response to property changes in
 associated action. | 
| void | addActionListener(ActionListener l)Adds the specified action listener to receive
 action events from this textfield. | 
| protected void | configurePropertiesFromAction(Action a)Sets the properties on this textfield to match those in the specified
  Action. | 
| protected PropertyChangeListener | createActionPropertyChangeListener(Action a)Creates and returns a  PropertyChangeListenerthat is
 responsible for listening for changes from the specifiedActionand updating the appropriate properties. | 
| protected Document | createDefaultModel()Creates the default implementation of the model
 to be used at construction if one isn't explicitly
 given. | 
| protected void | fireActionPerformed()Notifies all listeners that have registered interest for
 notification on this event type. | 
| AccessibleContext | getAccessibleContext()Gets the  AccessibleContextassociated with thisJTextField. | 
| Action | getAction()Returns the currently set  Actionfor thisActionEventsource, ornullif noActionis set. | 
| ActionListener[] | getActionListeners()Returns an array of all the  ActionListeners added
 to this JTextField with addActionListener(). | 
| Action[] | getActions()Fetches the command list for the editor. | 
| int | getColumns()Returns the number of columns in this  TextField. | 
| protected int | getColumnWidth()Returns the column width. | 
| int | getHorizontalAlignment()Returns the horizontal alignment of the text. | 
| BoundedRangeModel | getHorizontalVisibility()Gets the visibility of the text field. | 
| Dimension | getPreferredSize()Returns the preferred size  Dimensionsneeded for thisTextField. | 
| int | getScrollOffset()Gets the scroll offset, in pixels. | 
| String | getUIClassID()Gets the class ID for a UI. | 
| boolean | isValidateRoot()Calls to  revalidatethat come from within the
 textfield itself will
 be handled by validating the textfield, unless the textfield
 is contained within aJViewport,
 in which case this returns false. | 
| protected String | paramString()Returns a string representation of this  JTextField. | 
| void | postActionEvent()Processes action events occurring on this textfield by
 dispatching them to any registered  ActionListenerobjects. | 
| void | removeActionListener(ActionListener l)Removes the specified action listener so that it no longer
 receives action events from this textfield. | 
| void | scrollRectToVisible(Rectangle r)Scrolls the field left or right. | 
| void | setAction(Action a)Sets the  Actionfor theActionEventsource. | 
| void | setActionCommand(String command)Sets the command string used for action events. | 
| void | setColumns(int columns)Sets the number of columns in this  TextField,
 and then invalidate the layout. | 
| void | setDocument(Document doc)Associates the editor with a text document. | 
| void | setFont(Font f)Sets the current font. | 
| void | setHorizontalAlignment(int alignment)Sets the horizontal alignment of the text. | 
| void | setScrollOffset(int scrollOffset)Sets the scroll offset, in pixels. | 
addCaretListener, addInputMethodListener, addKeymap, copy, cut, fireCaretUpdate, getCaret, getCaretColor, getCaretListeners, getCaretPosition, getDisabledTextColor, getDocument, getDragEnabled, getDropLocation, getDropMode, getFocusAccelerator, getHighlighter, getInputMethodRequests, getKeymap, getKeymap, getMargin, getNavigationFilter, getPreferredScrollableViewportSize, getPrintable, getScrollableBlockIncrement, getScrollableTracksViewportHeight, getScrollableTracksViewportWidth, getScrollableUnitIncrement, getSelectedText, getSelectedTextColor, getSelectionColor, getSelectionEnd, getSelectionStart, getText, getText, getToolTipText, getUI, isEditable, loadKeymap, modelToView, moveCaretPosition, paste, print, print, print, processInputMethodEvent, read, removeCaretListener, removeKeymap, removeNotify, replaceSelection, restoreComposedText, saveComposedText, select, selectAll, setCaret, setCaretColor, setCaretPosition, setComponentOrientation, setDisabledTextColor, setDragEnabled, setDropMode, setEditable, setFocusAccelerator, setHighlighter, setKeymap, setMargin, setNavigationFilter, setSelectedTextColor, setSelectionColor, setSelectionEnd, setSelectionStart, setText, setUI, updateUI, viewToModel, writeaddAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, updateadd, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTreeaction, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCyclepublic static final String notifyAction
public JTextField()
TextField.  A default model is created,
 the initial string is null,
 and the number of columns is set to 0.public JTextField(String text)
TextField initialized with the
 specified text. A default model is created and the number of
 columns is 0.text - the text to be displayed, or nullpublic JTextField(int columns)
TextField with the specified
 number of columns.
 A default model is created and the initial string is set to
 null.columns - the number of columns to use to calculate
   the preferred width; if columns is set to zero, the
   preferred width will be whatever naturally results from
   the component implementationpublic JTextField(String text, int columns)
TextField initialized with the
 specified text and columns.  A default model is created.text - the text to be displayed, or nullcolumns - the number of columns to use to calculate
   the preferred width; if columns is set to zero, the
   preferred width will be whatever naturally results from
   the component implementationpublic JTextField(Document doc, String text, int columns)
JTextField that uses the given text
 storage model and the given number of columns.
 This is the constructor through which the other constructors feed.
 If the document is null, a default model is created.doc - the text storage to use; if this is null,
          a default will be provided by calling the
          createDefaultModel methodtext - the initial string to display, or nullcolumns - the number of columns to use to calculate
   the preferred width >= 0; if columns
   is set to zero, the preferred width will be whatever
   naturally results from the component implementationIllegalArgumentException - if columns < 0public String getUIClassID()
getUIClassID in class JComponentJComponent.getUIClassID(), 
UIDefaults.getUI(javax.swing.JComponent)public void setDocument(Document doc)
setDocument in class JTextComponentdoc - the document to display/editJTextComponent.getDocument()public boolean isValidateRoot()
revalidate that come from within the
 textfield itself will
 be handled by validating the textfield, unless the textfield
 is contained within a JViewport,
 in which case this returns false.isValidateRoot in class JComponentJViewPort
          return false, otherwise return trueJComponent.revalidate(), 
JComponent.isValidateRoot(), 
Container.isValidateRoot()public int getHorizontalAlignment()
JTextField.LEFT
 JTextField.CENTER
 JTextField.RIGHT
 JTextField.LEADING
 JTextField.TRAILING
 public void setHorizontalAlignment(int alignment)
JTextField.LEFT
 JTextField.CENTER
 JTextField.RIGHT
 JTextField.LEADING
 JTextField.TRAILING
 invalidate and repaint are called when the
 alignment is set,
 and a PropertyChange event ("horizontalAlignment") is fired.alignment - the alignmentIllegalArgumentException - if alignment
  is not a valid keyprotected Document createDefaultModel()
PlainDocument is returned.public int getColumns()
TextField.public void setColumns(int columns)
TextField,
 and then invalidate the layout.columns - the number of columns >= 0IllegalArgumentException - if columns
          is less than 0protected int getColumnWidth()
public Dimension getPreferredSize()
Dimensions needed for this
 TextField.  If a non-zero number of columns has been
 set, the width is set to the columns multiplied by
 the column width.getPreferredSize in class JComponentJComponent.setPreferredSize(java.awt.Dimension), 
ComponentUIpublic void setFont(Font f)
revalidate is called after setting the font.setFont in class JComponentf - the new fontComponent.getFont()public void addActionListener(ActionListener l)
l - the action listener to be addedpublic void removeActionListener(ActionListener l)
l - the action listener to be removedpublic ActionListener[] getActionListeners()
ActionListeners added
 to this JTextField with addActionListener().ActionListeners added or an empty
         array if no listeners have been addedprotected void fireActionPerformed()
EventListenerListpublic void setActionCommand(String command)
command - the command stringpublic void setAction(Action a)
Action for the ActionEvent source.
 The new Action replaces
 any previously set Action but does not affect
 ActionListeners independently
 added with addActionListener.
 If the Action is already a registered
 ActionListener
 for the ActionEvent source, it is not re-registered.
 
 Setting the Action results in immediately changing
 all the properties described in 
 Swing Components Supporting Action.
 Subsequently, the textfield's properties are automatically updated
 as the Action's properties change.
 
 This method uses three other methods to set
 and help track the Action's property values.
 It uses the configurePropertiesFromAction method
 to immediately change the textfield's properties.
 To track changes in the Action's property values,
 this method registers the PropertyChangeListener
 returned by createActionPropertyChangeListener. The
 default PropertyChangeListener invokes the
 actionPropertyChanged method when a property in the
 Action changes.
a - the Action for the JTextField,
          or nullAction, 
getAction(), 
configurePropertiesFromAction(javax.swing.Action), 
createActionPropertyChangeListener(javax.swing.Action), 
actionPropertyChanged(javax.swing.Action, java.lang.String)public Action getAction()
Action for this
 ActionEvent source, or null
 if no Action is set.Action for this ActionEvent source,
          or nullAction, 
setAction(javax.swing.Action)protected void configurePropertiesFromAction(Action a)
Action.  Refer to 
 Swing Components Supporting Action for more
 details as to which properties this sets.a - the Action from which to get the properties,
          or nullAction, 
setAction(javax.swing.Action)protected void actionPropertyChanged(Action action, String propertyName)
PropertyChangeListener returned from
 createActionPropertyChangeListener. Subclasses do not normally
 need to invoke this. Subclasses that support additional Action
 properties should override this and
 configurePropertiesFromAction.
 
 Refer to the table at 
 Swing Components Supporting Action for a list of
 the properties this method sets.
action - the Action associated with this textfieldpropertyName - the name of the property that changedAction, 
configurePropertiesFromAction(javax.swing.Action)protected PropertyChangeListener createActionPropertyChangeListener(Action a)
PropertyChangeListener that is
 responsible for listening for changes from the specified
 Action and updating the appropriate properties.
 
 Warning: If you subclass this do not create an anonymous
 inner class.  If you do the lifetime of the textfield will be tied to
 that of the Action.
a - the textfield's actionAction, 
setAction(javax.swing.Action)public Action[] getActions()
getActions in class JTextComponentpublic void postActionEvent()
ActionListener objects.
 This is normally called by the controller registered with
 textfield.public BoundedRangeModel getHorizontalVisibility()
 The fields look-and-feel implementation manages
 the values of the minimum, maximum, and extent
 properties on the BoundedRangeModel.
BoundedRangeModelpublic int getScrollOffset()
public void setScrollOffset(int scrollOffset)
scrollOffset - the offset >= 0public void scrollRectToVisible(Rectangle r)
scrollRectToVisible in class JComponentr - the region to scrollJViewportprotected String paramString()
JTextField.
 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.paramString in class JTextComponentJTextFieldpublic AccessibleContext getAccessibleContext()
AccessibleContext associated with this
 JTextField. For JTextFields,
 the AccessibleContext takes the form of an
 AccessibleJTextField.
 A new AccessibleJTextField instance is created
 if necessary.getAccessibleContext in interface AccessiblegetAccessibleContext in class JTextComponentAccessibleJTextField that serves as the
         AccessibleContext of this JTextField Submit a bug or feature 
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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