https://openjdk.java.net/ 
/*
 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package javax.swing;

import java.awt.*;
import java.awt.event.*;
import java.beans.JavaBean;
import java.beans.BeanProperty;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.text.*;
import javax.swing.event.*;
import javax.accessibility.*;

import java.io.ObjectOutputStream;
import java.io.IOException;
import java.io.Serializable;


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 JavaBeans™
has been added to the java.beans package. Please see XMLEncoder. 
Author: Timothy Prinzing
See Also:
Since:1.2
/**
 * <code>JTextField</code> is a lightweight component that allows the editing
 * of a single line of text.
 * For information on and examples of using text fields,
 * see
 * <a href="http://docs.oracle.com/javase/tutorial/uiswing/components/textfield.html">How to Use Text Fields</a>
 * in <em>The Java Tutorial.</em>
 *
 * <p>
 * <code>JTextField</code> is intended to be source-compatible
 * with <code>java.awt.TextField</code> where it is reasonable to do so.  This
 * component has capabilities not found in the <code>java.awt.TextField</code>
 * class.  The superclass should be consulted for additional capabilities.
 * <p>
 * <code>JTextField</code> has a method to establish the string used as the
 * command string for the action event that gets fired.  The
 * <code>java.awt.TextField</code> used the text of the field as the command
 * string for the <code>ActionEvent</code>.
 * <code>JTextField</code> will use the command
 * string set with the <code>setActionCommand</code> method if not <code>null</code>,
 * otherwise it will use the text of the field as a compatibility with
 * <code>java.awt.TextField</code>.
 * <p>
 * The method <code>setEchoChar</code> and <code>getEchoChar</code>
 * 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 <code>JPasswordField</code>
 * extends <code>JTextField</code> to provide this service with an independently
 * pluggable look-and-feel.
 * <p>
 * The <code>java.awt.TextField</code> could be monitored for changes by adding
 * a <code>TextListener</code> for <code>TextEvent</code>'s.
 * In the <code>JTextComponent</code> based
 * components, changes are broadcasted from the model via a
 * <code>DocumentEvent</code> to <code>DocumentListeners</code>.
 * The <code>DocumentEvent</code> gives
 * the location of the change and the kind of change if desired.
 * The code fragment might look something like:
 * <pre><code>
 * &nbsp;   DocumentListener myListener = ??;
 * &nbsp;   JTextField myArea = ??;
 * &nbsp;   myArea.getDocument().addDocumentListener(myListener);
 * </code></pre>
 * <p>
 * The horizontal alignment of <code>JTextField</code> 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 <code>setHorizontalAlignment</code>
 * and <code>getHorizontalAlignment</code> methods.  The default
 * is to be leading justified.
 * <p>
 * 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.
 * <p>
 * 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.
 * <pre><code>

&nbsp;public class UpperCaseField extends JTextField {
&nbsp;
&nbsp;    public UpperCaseField(int cols) {
&nbsp;        super(cols);
&nbsp;    }
&nbsp;
&nbsp;    protected Document createDefaultModel() {
&nbsp;        return new UpperCaseDocument();
&nbsp;    }
&nbsp;
&nbsp;    static class UpperCaseDocument extends PlainDocument {
&nbsp;
&nbsp;        public void insertString(int offs, String str, AttributeSet a)
&nbsp;            throws BadLocationException {
&nbsp;
&nbsp;            if (str == null) {
&nbsp;                return;
&nbsp;            }
&nbsp;            char[] upper = str.toCharArray();
&nbsp;            for (int i = 0; i &lt; upper.length; i++) {
&nbsp;                upper[i] = Character.toUpperCase(upper[i]);
&nbsp;            }
&nbsp;            super.insertString(offs, new String(upper), a);
&nbsp;        }
&nbsp;    }
&nbsp;}

 * </code></pre>
 * <p>
 * <strong>Warning:</strong> Swing is not thread safe. For more
 * information see <a
 * href="package-summary.html#threading">Swing's Threading
 * Policy</a>.
 * <p>
 * <strong>Warning:</strong>
 * 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 JavaBeans&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author  Timothy Prinzing
 * @see #setActionCommand
 * @see JPasswordField
 * @see #addActionListener
 * @since 1.2
 */
@JavaBean(defaultProperty = "UIClassID", description = "A component which allows for the editing of a single line of text.")
@SwingContainer(false)
@SuppressWarnings("serial") // Same-version serialization only
public class JTextField extends JTextComponent implements SwingConstants {

    
Constructs a new TextField.  A default model is created,
the initial string is null,
and the number of columns is set to 0.

/**
     * Constructs a new <code>TextField</code>.  A default model is created,
     * the initial string is <code>null</code>,
     * and the number of columns is set to 0.
     */
    public JTextField() {
        this(null, null, 0);
    }

    
Constructs a new TextField initialized with the
specified text. A default model is created and the number of
columns is 0.

Params:
  • text – the text to be displayed, or null
/**
     * Constructs a new <code>TextField</code> initialized with the
     * specified text. A default model is created and the number of
     * columns is 0.
     *
     * @param text the text to be displayed, or <code>null</code>
     */
    public JTextField(String text) {
        this(null, text, 0);
    }

    
Constructs a new empty TextField with the specified
number of columns.
A default model is created and the initial string is set to
null.

Params:
  • 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 implementation
/**
     * Constructs a new empty <code>TextField</code> with the specified
     * number of columns.
     * A default model is created and the initial string is set to
     * <code>null</code>.
     *
     * @param 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 implementation
     */
    public JTextField(int columns) {
        this(null, null, columns);
    }

    
Constructs a new TextField initialized with the
specified text and columns.  A default model is created.

Params:
  • text – the text to be displayed, or 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 implementation
/**
     * Constructs a new <code>TextField</code> initialized with the
     * specified text and columns.  A default model is created.
     *
     * @param text the text to be displayed, or <code>null</code>
     * @param 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 implementation
     */
    public JTextField(String text, int columns) {
        this(null, text, columns);
    }

    
Constructs a new 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.

Params:
  • doc –  the text storage to use; if this is null,
         a default will be provided by calling the
         createDefaultModel method
  • text –  the initial string to display, or null
  • columns –  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 implementation
Throws:
/**
     * Constructs a new <code>JTextField</code> 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 <code>null</code>, a default model is created.
     *
     * @param doc  the text storage to use; if this is <code>null</code>,
     *          a default will be provided by calling the
     *          <code>createDefaultModel</code> method
     * @param text  the initial string to display, or <code>null</code>
     * @param columns  the number of columns to use to calculate
     *   the preferred width &gt;= 0; if <code>columns</code>
     *   is set to zero, the preferred width will be whatever
     *   naturally results from the component implementation
     * @exception IllegalArgumentException if <code>columns</code> &lt; 0
     */
    public JTextField(Document doc, String text, int columns) {
        if (columns < 0) {
            throw new IllegalArgumentException("columns less than zero.");
        }
        visibility = new DefaultBoundedRangeModel();
        visibility.addChangeListener(new ScrollRepainter());
        this.columns = columns;
        if (doc == null) {
            doc = createDefaultModel();
        }
        setDocument(doc);
        if (text != null) {
            setText(text);
        }
    }

    
Gets the class ID for a UI.

See Also:
Returns:the string "TextFieldUI"
/**
     * Gets the class ID for a UI.
     *
     * @return the string "TextFieldUI"
     * @see JComponent#getUIClassID
     * @see UIDefaults#getUI
     */
    @BeanProperty(bound = false)
    public String getUIClassID() {
        return uiClassID;
    }


    
Associates the editor with a text document.
The currently registered factory is used to build a view for
the document, which gets displayed by the editor after revalidation.
A PropertyChange event ("document") is propagated to each listener.

Params:
  • doc –  the document to display/edit
See Also:
/**
     * Associates the editor with a text document.
     * The currently registered factory is used to build a view for
     * the document, which gets displayed by the editor after revalidation.
     * A PropertyChange event ("document") is propagated to each listener.
     *
     * @param doc  the document to display/edit
     * @see #getDocument
     */
    @BeanProperty(expert = true, description
            = "the text document model")
    public void setDocument(Document doc) {
        if (doc != null) {
            doc.putProperty("filterNewlines", Boolean.TRUE);
        }
        super.setDocument(doc);
    }

    
Calls to 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.

See Also:
Returns:if the parent of this textfield is a JViewPort
         return false, otherwise return true
/**
     * Calls to <code>revalidate</code> that come from within the
     * textfield itself will
     * be handled by validating the textfield, unless the textfield
     * is contained within a <code>JViewport</code>,
     * in which case this returns false.
     *
     * @return if the parent of this textfield is a <code>JViewPort</code>
     *          return false, otherwise return true
     *
     * @see JComponent#revalidate
     * @see JComponent#isValidateRoot
     * @see java.awt.Container#isValidateRoot
     */
    @Override
    public boolean isValidateRoot() {
        return !(SwingUtilities.getUnwrappedParent(this) instanceof JViewport);
    }


    
Returns the horizontal alignment of the text.
Valid keys are:

    

  • JTextField.LEFT

  • JTextField.CENTER

  • JTextField.RIGHT

  • JTextField.LEADING

  • JTextField.TRAILING



Returns:the horizontal alignment
/**
     * Returns the horizontal alignment of the text.
     * Valid keys are:
     * <ul>
     * <li><code>JTextField.LEFT</code>
     * <li><code>JTextField.CENTER</code>
     * <li><code>JTextField.RIGHT</code>
     * <li><code>JTextField.LEADING</code>
     * <li><code>JTextField.TRAILING</code>
     * </ul>
     *
     * @return the horizontal alignment
     */
    public int getHorizontalAlignment() {
        return horizontalAlignment;
    }

    
Sets the horizontal alignment of the text.
Valid keys are:

    

  • 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.

Params:
  • alignment – the alignment
Throws:
/**
     * Sets the horizontal alignment of the text.
     * Valid keys are:
     * <ul>
     * <li><code>JTextField.LEFT</code>
     * <li><code>JTextField.CENTER</code>
     * <li><code>JTextField.RIGHT</code>
     * <li><code>JTextField.LEADING</code>
     * <li><code>JTextField.TRAILING</code>
     * </ul>
     * <code>invalidate</code> and <code>repaint</code> are called when the
     * alignment is set,
     * and a <code>PropertyChange</code> event ("horizontalAlignment") is fired.
     *
     * @param alignment the alignment
     * @exception IllegalArgumentException if <code>alignment</code>
     *  is not a valid key
     */
     @BeanProperty(preferred = true, enumerationValues = {
             "JTextField.LEFT",
             "JTextField.CENTER",
             "JTextField.RIGHT",
             "JTextField.LEADING",
             "JTextField.TRAILING"}, description
             = "Set the field alignment to LEFT, CENTER, RIGHT, LEADING (the default) or TRAILING")
     public void setHorizontalAlignment(int alignment) {
        if (alignment == horizontalAlignment) return;
        int oldValue = horizontalAlignment;
        if ((alignment == LEFT) || (alignment == CENTER) ||
            (alignment == RIGHT)|| (alignment == LEADING) ||
            (alignment == TRAILING)) {
            horizontalAlignment = alignment;
        } else {
            throw new IllegalArgumentException("horizontalAlignment");
        }
        firePropertyChange("horizontalAlignment", oldValue, horizontalAlignment);
        invalidate();
        repaint();
    }

    
Creates the default implementation of the model
to be used at construction if one isn't explicitly
given.  An instance of PlainDocument is returned.

Returns:the default model implementation
/**
     * Creates the default implementation of the model
     * to be used at construction if one isn't explicitly
     * given.  An instance of <code>PlainDocument</code> is returned.
     *
     * @return the default model implementation
     */
    protected Document createDefaultModel() {
        return new PlainDocument();
    }

    
Returns the number of columns in this TextField.

Returns:the number of columns >= 0
/**
     * Returns the number of columns in this <code>TextField</code>.
     *
     * @return the number of columns &gt;= 0
     */
    public int getColumns() {
        return columns;
    }

    
Sets the number of columns in this TextField,
and then invalidate the layout.

Params:
  • columns – the number of columns >= 0
Throws:
/**
     * Sets the number of columns in this <code>TextField</code>,
     * and then invalidate the layout.
     *
     * @param columns the number of columns &gt;= 0
     * @exception IllegalArgumentException if <code>columns</code>
     *          is less than 0
     */
    @BeanProperty(bound = false, description
            = "the number of columns preferred for display")
    public void setColumns(int columns) {
        int oldVal = this.columns;
        if (columns < 0) {
            throw new IllegalArgumentException("columns less than zero.");
        }
        if (columns != oldVal) {
            this.columns = columns;
            invalidate();
        }
    }

    
Returns the column width.
The meaning of what a column is can be considered a fairly weak
notion for some fonts.  This method is used to define the width
of a column.  By default this is defined to be the width of the
character m for the font used.  This method can be
redefined to be some alternative amount

Returns:the column width >= 1
/**
     * Returns the column width.
     * The meaning of what a column is can be considered a fairly weak
     * notion for some fonts.  This method is used to define the width
     * of a column.  By default this is defined to be the width of the
     * character <em>m</em> for the font used.  This method can be
     * redefined to be some alternative amount
     *
     * @return the column width &gt;= 1
     */
    protected int getColumnWidth() {
        if (columnWidth == 0) {
            FontMetrics metrics = getFontMetrics(getFont());
            columnWidth = metrics.charWidth('m');
        }
        return columnWidth;
    }

    
Returns the preferred size 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.

Returns:the dimension of this textfield
/**
     * Returns the preferred size <code>Dimensions</code> needed for this
     * <code>TextField</code>.  If a non-zero number of columns has been
     * set, the width is set to the columns multiplied by
     * the column width.
     *
     * @return the dimension of this textfield
     */
    public Dimension getPreferredSize() {
        Dimension size = super.getPreferredSize();
        if (columns != 0) {
            Insets insets = getInsets();
            size.width = columns * getColumnWidth() +
                insets.left + insets.right;
        }
        return size;
    }

    
Sets the current font.  This removes cached row height and column
width so the new font will be reflected.
revalidate is called after setting the font.

Params:
  • f – the new font
/**
     * Sets the current font.  This removes cached row height and column
     * width so the new font will be reflected.
     * <code>revalidate</code> is called after setting the font.
     *
     * @param f the new font
     */
    public void setFont(Font f) {
        super.setFont(f);
        columnWidth = 0;
    }

    
Adds the specified action listener to receive
action events from this textfield.

Params:
  • l – the action listener to be added
/**
     * Adds the specified action listener to receive
     * action events from this textfield.
     *
     * @param l the action listener to be added
     */
    public synchronized void addActionListener(ActionListener l) {
        listenerList.add(ActionListener.class, l);
    }

    
Removes the specified action listener so that it no longer
receives action events from this textfield.

Params:
  • l – the action listener to be removed
/**
     * Removes the specified action listener so that it no longer
     * receives action events from this textfield.
     *
     * @param l the action listener to be removed
     */
    public synchronized void removeActionListener(ActionListener l) {
        if ((l != null) && (getAction() == l)) {
            setAction(null);
        } else {
            listenerList.remove(ActionListener.class, l);
        }
    }

    
Returns an array of all the ActionListeners added
to this JTextField with addActionListener().

Returns:all of the ActionListeners added or an empty
        array if no listeners have been added
Since:1.4
/**
     * Returns an array of all the <code>ActionListener</code>s added
     * to this JTextField with addActionListener().
     *
     * @return all of the <code>ActionListener</code>s added or an empty
     *         array if no listeners have been added
     * @since 1.4
     */
    @BeanProperty(bound = false)
    public synchronized ActionListener[] getActionListeners() {
        return listenerList.getListeners(ActionListener.class);
    }

    
Notifies all listeners that have registered interest for
notification on this event type.  The event instance
is lazily created.
The listener list is processed in last to
first order.

See Also:
  • EventListenerList
/**
     * Notifies all listeners that have registered interest for
     * notification on this event type.  The event instance
     * is lazily created.
     * The listener list is processed in last to
     * first order.
     * @see EventListenerList
     */
    @SuppressWarnings("deprecation")
    protected void fireActionPerformed() {
        // Guaranteed to return a non-null array
        Object[] listeners = listenerList.getListenerList();
        int modifiers = 0;
        AWTEvent currentEvent = EventQueue.getCurrentEvent();
        if (currentEvent instanceof InputEvent) {
            modifiers = ((InputEvent)currentEvent).getModifiers();
        } else if (currentEvent instanceof ActionEvent) {
            modifiers = ((ActionEvent)currentEvent).getModifiers();
        }
        ActionEvent e =
            new ActionEvent(this, ActionEvent.ACTION_PERFORMED,
                            (command != null) ? command : getText(),
                            EventQueue.getMostRecentEventTime(), modifiers);

        // Process the listeners last to first, notifying
        // those that are interested in this event
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==ActionListener.class) {
                ((ActionListener)listeners[i+1]).actionPerformed(e);
            }
        }
    }

    
Sets the command string used for action events.

Params:
  • command – the command string
/**
     * Sets the command string used for action events.
     *
     * @param command the command string
     */
    public void setActionCommand(String command) {
        this.command = command;
    }

    private Action action;
    private PropertyChangeListener actionPropertyChangeListener;

    
Sets the 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. 
Params:
  • a – the Action for the JTextField,
         or null
See Also:
Since:1.3
/**
     * Sets the <code>Action</code> for the <code>ActionEvent</code> source.
     * The new <code>Action</code> replaces
     * any previously set <code>Action</code> but does not affect
     * <code>ActionListeners</code> independently
     * added with <code>addActionListener</code>.
     * If the <code>Action</code> is already a registered
     * <code>ActionListener</code>
     * for the <code>ActionEvent</code> source, it is not re-registered.
     * <p>
     * Setting the <code>Action</code> results in immediately changing
     * all the properties described in <a href="Action.html#buttonActions">
     * Swing Components Supporting <code>Action</code></a>.
     * Subsequently, the textfield's properties are automatically updated
     * as the <code>Action</code>'s properties change.
     * <p>
     * This method uses three other methods to set
     * and help track the <code>Action</code>'s property values.
     * It uses the <code>configurePropertiesFromAction</code> method
     * to immediately change the textfield's properties.
     * To track changes in the <code>Action</code>'s property values,
     * this method registers the <code>PropertyChangeListener</code>
     * returned by <code>createActionPropertyChangeListener</code>. The
     * default {@code PropertyChangeListener} invokes the
     * {@code actionPropertyChanged} method when a property in the
     * {@code Action} changes.
     *
     * @param a the <code>Action</code> for the <code>JTextField</code>,
     *          or <code>null</code>
     * @since 1.3
     * @see Action
     * @see #getAction
     * @see #configurePropertiesFromAction
     * @see #createActionPropertyChangeListener
     * @see #actionPropertyChanged
     */
    @BeanProperty(visualUpdate = true, description
            = "the Action instance connected with this ActionEvent source")
    public void setAction(Action a) {
        Action oldValue = getAction();
        if (action==null || !action.equals(a)) {
            action = a;
            if (oldValue!=null) {
                removeActionListener(oldValue);
                oldValue.removePropertyChangeListener(actionPropertyChangeListener);
                actionPropertyChangeListener = null;
            }
            configurePropertiesFromAction(action);
            if (action!=null) {
                // Don't add if it is already a listener
                if (!isListener(ActionListener.class, action)) {
                    addActionListener(action);
                }
                // Reverse linkage:
                actionPropertyChangeListener = createActionPropertyChangeListener(action);
                action.addPropertyChangeListener(actionPropertyChangeListener);
            }
            firePropertyChange("action", oldValue, action);
        }
    }

    private boolean isListener(Class<?> c, ActionListener a) {
        boolean isListener = false;
        Object[] listeners = listenerList.getListenerList();
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==c && listeners[i+1]==a) {
                    isListener=true;
            }
        }
        return isListener;
    }

    
Returns the currently set Action for this
ActionEvent source, or null
if no Action is set.

See Also:
Returns:the Action for this ActionEvent source,
         or null
Since:1.3
/**
     * Returns the currently set <code>Action</code> for this
     * <code>ActionEvent</code> source, or <code>null</code>
     * if no <code>Action</code> is set.
     *
     * @return the <code>Action</code> for this <code>ActionEvent</code> source,
     *          or <code>null</code>
     * @since 1.3
     * @see Action
     * @see #setAction
     */
    public Action getAction() {
        return action;
    }

    
Sets the properties on this textfield to match those in the specified
Action.  Refer to 
Swing Components Supporting Action for more
details as to which properties this sets.

Params:
  • a – the Action from which to get the properties,
         or null
See Also:
Since:1.3
/**
     * Sets the properties on this textfield to match those in the specified
     * <code>Action</code>.  Refer to <a href="Action.html#buttonActions">
     * Swing Components Supporting <code>Action</code></a> for more
     * details as to which properties this sets.
     *
     * @param a the <code>Action</code> from which to get the properties,
     *          or <code>null</code>
     * @since 1.3
     * @see Action
     * @see #setAction
     */
    protected void configurePropertiesFromAction(Action a) {
        AbstractAction.setEnabledFromAction(this, a);
        AbstractAction.setToolTipTextFromAction(this, a);
        setActionCommandFromAction(a);
    }

    
Updates the textfield's state in response to property changes in associated action. This method is invoked from the 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.

Params:
  • action – the Action associated with this textfield
  • propertyName – the name of the property that changed
See Also:
Since:1.6
/**
     * Updates the textfield's state in response to property changes in
     * associated action. This method is invoked from the
     * {@code PropertyChangeListener} returned from
     * {@code createActionPropertyChangeListener}. Subclasses do not normally
     * need to invoke this. Subclasses that support additional {@code Action}
     * properties should override this and
     * {@code configurePropertiesFromAction}.
     * <p>
     * Refer to the table at <a href="Action.html#buttonActions">
     * Swing Components Supporting <code>Action</code></a> for a list of
     * the properties this method sets.
     *
     * @param action the <code>Action</code> associated with this textfield
     * @param propertyName the name of the property that changed
     * @since 1.6
     * @see Action
     * @see #configurePropertiesFromAction
     */
    protected void actionPropertyChanged(Action action, String propertyName) {
        if (propertyName == Action.ACTION_COMMAND_KEY) {
            setActionCommandFromAction(action);
        } else if (propertyName == "enabled") {
            AbstractAction.setEnabledFromAction(this, action);
        } else if (propertyName == Action.SHORT_DESCRIPTION) {
            AbstractAction.setToolTipTextFromAction(this, action);
        }
    }

    private void setActionCommandFromAction(Action action) {
        setActionCommand((action == null) ? null :
                         (String)action.getValue(Action.ACTION_COMMAND_KEY));
    }

    
Creates and returns 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.

Params:
  • a – the textfield's action
See Also:
Returns:a PropertyChangeListener that is responsible for listening for changes from the specified Action and updating the appropriate properties
Since:1.3
/**
     * Creates and returns a <code>PropertyChangeListener</code> that is
     * responsible for listening for changes from the specified
     * <code>Action</code> and updating the appropriate properties.
     * <p>
     * <b>Warning:</b> 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 <code>Action</code>.
     *
     * @param a the textfield's action
     * @return a {@code PropertyChangeListener} that is responsible for
     *         listening for changes from the specified {@code Action} and
     *         updating the appropriate properties
     * @since 1.3
     * @see Action
     * @see #setAction
     */
    protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
        return new TextFieldActionPropertyChangeListener(this, a);
    }

    private static class TextFieldActionPropertyChangeListener extends
                         ActionPropertyChangeListener<JTextField> {
        TextFieldActionPropertyChangeListener(JTextField tf, Action a) {
            super(tf, a);
        }

        protected void actionPropertyChanged(JTextField textField,
                                             Action action,
                                             PropertyChangeEvent e) {
            if (AbstractAction.shouldReconfigure(e)) {
                textField.configurePropertiesFromAction(action);
            } else {
                textField.actionPropertyChanged(action, e.getPropertyName());
            }
        }
    }

    
Fetches the command list for the editor.  This is
the list of commands supported by the plugged-in UI
augmented by the collection of commands that the
editor itself supports.  These are useful for binding
to events, such as in a keymap.

Returns:the command list
/**
     * Fetches the command list for the editor.  This is
     * the list of commands supported by the plugged-in UI
     * augmented by the collection of commands that the
     * editor itself supports.  These are useful for binding
     * to events, such as in a keymap.
     *
     * @return the command list
     */
    @BeanProperty(bound = false)
    public Action[] getActions() {
        return TextAction.augmentList(super.getActions(), defaultActions);
    }

    
Processes action events occurring on this textfield by
dispatching them to any registered ActionListener objects.
This is normally called by the controller registered with
textfield.

/**
     * Processes action events occurring on this textfield by
     * dispatching them to any registered <code>ActionListener</code> objects.
     * This is normally called by the controller registered with
     * textfield.
     */
    public void postActionEvent() {
        fireActionPerformed();
    }

    // --- Scrolling support -----------------------------------

    
Gets the visibility of the text field.  This can
be adjusted to change the location of the visible
area if the size of the field is greater than
the area that was allocated to the field.


The fields look-and-feel implementation manages
the values of the minimum, maximum, and extent
properties on the BoundedRangeModel.

See Also:
Returns:the visibility
/**
     * Gets the visibility of the text field.  This can
     * be adjusted to change the location of the visible
     * area if the size of the field is greater than
     * the area that was allocated to the field.
     *
     * <p>
     * The fields look-and-feel implementation manages
     * the values of the minimum, maximum, and extent
     * properties on the <code>BoundedRangeModel</code>.
     *
     * @return the visibility
     * @see BoundedRangeModel
     */
    @BeanProperty(bound = false)
    public BoundedRangeModel getHorizontalVisibility() {
        return visibility;
    }

    
Gets the scroll offset, in pixels.

Returns:the offset >= 0
/**
     * Gets the scroll offset, in pixels.
     *
     * @return the offset &gt;= 0
     */
    public int getScrollOffset() {
        return visibility.getValue();
    }

    
Sets the scroll offset, in pixels.

Params:
  • scrollOffset – the offset >= 0
/**
     * Sets the scroll offset, in pixels.
     *
     * @param scrollOffset the offset &gt;= 0
     */
    public void setScrollOffset(int scrollOffset) {
        visibility.setValue(scrollOffset);
    }

    
Scrolls the field left or right.

Params:
  • r – the region to scroll
/**
     * Scrolls the field left or right.
     *
     * @param r the region to scroll
     */
    public void scrollRectToVisible(Rectangle r) {
        // convert to coordinate system of the bounded range
        Insets i = getInsets();
        int x0 = r.x + visibility.getValue() - i.left;
        int x1 = x0 + r.width;
        if (x0 < visibility.getValue()) {
            // Scroll to the left
            visibility.setValue(x0);
        } else if(x1 > visibility.getValue() + visibility.getExtent()) {
            // Scroll to the right
            visibility.setValue(x1 - visibility.getExtent());
        }
    }

    
Returns true if the receiver has an ActionListener
installed.

/**
     * Returns true if the receiver has an <code>ActionListener</code>
     * installed.
     */
    boolean hasActionListener() {
        // Guaranteed to return a non-null array
        Object[] listeners = listenerList.getListenerList();
        // Process the listeners last to first, notifying
        // those that are interested in this event
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==ActionListener.class) {
                return true;
            }
        }
        return false;
    }

    // --- variables -------------------------------------------

    
Name of the action to send notification that the
contents of the field have been accepted.  Typically
this is bound to a carriage-return.

/**
     * Name of the action to send notification that the
     * contents of the field have been accepted.  Typically
     * this is bound to a carriage-return.
     */
    public static final String notifyAction = "notify-field-accept";

    private BoundedRangeModel visibility;
    private int horizontalAlignment = LEADING;
    private int columns;
    private int columnWidth;
    private String command;

    private static final Action[] defaultActions = {
        new NotifyAction()
    };

    
See Also:
/**
     * @see #getUIClassID
     * @see #readObject
     */
    private static final String uiClassID = "TextFieldUI";

    // --- Action implementations -----------------------------------

    // Note that JFormattedTextField.CommitAction extends this
    static class NotifyAction extends TextAction {

        NotifyAction() {
            super(notifyAction);
        }

        public void actionPerformed(ActionEvent e) {
            JTextComponent target = getFocusedComponent();
            if (target instanceof JTextField) {
                JTextField field = (JTextField) target;
                field.postActionEvent();
            }
        }

        public boolean isEnabled() {
            JTextComponent target = getFocusedComponent();
            if (target instanceof JTextField) {
                return ((JTextField)target).hasActionListener();
            }
            return false;
        }
    }

    class ScrollRepainter implements ChangeListener, Serializable {

        public void stateChanged(ChangeEvent e) {
            repaint();
        }

    }


    
See readObject and writeObject in
JComponent for more
information about serialization in Swing.

/**
     * See <code>readObject</code> and <code>writeObject</code> in
     * <code>JComponent</code> for more
     * information about serialization in Swing.
     */
    private void writeObject(ObjectOutputStream s) throws IOException {
        s.defaultWriteObject();
        if (getUIClassID().equals(uiClassID)) {
            byte count = JComponent.getWriteObjCounter(this);
            JComponent.setWriteObjCounter(this, --count);
            if (count == 0 && ui != null) {
                ui.installUI(this);
            }
        }
    }


    
Returns a string representation of this 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.

Returns: a string representation of this JTextField
/**
     * Returns a string representation of this <code>JTextField</code>.
     * 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 <code>null</code>.
     *
     * @return  a string representation of this <code>JTextField</code>
     */
    protected String paramString() {
        String horizontalAlignmentString;
        if (horizontalAlignment == LEFT) {
            horizontalAlignmentString = "LEFT";
        } else if (horizontalAlignment == CENTER) {
            horizontalAlignmentString = "CENTER";
        } else if (horizontalAlignment == RIGHT) {
            horizontalAlignmentString = "RIGHT";
        } else if (horizontalAlignment == LEADING) {
            horizontalAlignmentString = "LEADING";
        } else if (horizontalAlignment == TRAILING) {
            horizontalAlignmentString = "TRAILING";
        } else horizontalAlignmentString = "";
        String commandString = (command != null ?
                                command : "");

        return super.paramString() +
        ",columns=" + columns +
        ",columnWidth=" + columnWidth +
        ",command=" + commandString +
        ",horizontalAlignment=" + horizontalAlignmentString;
    }


/////////////////
// Accessibility support
////////////////


    
Gets the AccessibleContext associated with this
JTextField. For JTextFields,
the AccessibleContext takes the form of an
AccessibleJTextField.
A new AccessibleJTextField instance is created
if necessary.

Returns:an AccessibleJTextField that serves as the
        AccessibleContext of this JTextField
/**
     * Gets the <code>AccessibleContext</code> associated with this
     * <code>JTextField</code>. For <code>JTextFields</code>,
     * the <code>AccessibleContext</code> takes the form of an
     * <code>AccessibleJTextField</code>.
     * A new <code>AccessibleJTextField</code> instance is created
     * if necessary.
     *
     * @return an <code>AccessibleJTextField</code> that serves as the
     *         <code>AccessibleContext</code> of this <code>JTextField</code>
     */
    @BeanProperty(bound = false)
    public AccessibleContext getAccessibleContext() {
        if (accessibleContext == null) {
            accessibleContext = new AccessibleJTextField();
        }
        return accessibleContext;
    }

    
This class implements accessibility support for the
JTextField class.  It provides an implementation of the
Java Accessibility API appropriate to text field user-interface
elements.


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 JavaBeans™
has been added to the java.beans package. Please see XMLEncoder. 
/**
     * This class implements accessibility support for the
     * <code>JTextField</code> class.  It provides an implementation of the
     * Java Accessibility API appropriate to text field user-interface
     * elements.
     * <p>
     * <strong>Warning:</strong>
     * 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 JavaBeans&trade;
     * has been added to the <code>java.beans</code> package.
     * Please see {@link java.beans.XMLEncoder}.
     */
    @SuppressWarnings("serial") // Same-version serialization only
    protected class AccessibleJTextField extends AccessibleJTextComponent {

        
Gets the state set of this object.

See Also:
Returns:an instance of AccessibleStateSet describing the states
of the object
/**
         * Gets the state set of this object.
         *
         * @return an instance of AccessibleStateSet describing the states
         * of the object
         * @see AccessibleState
         */
        public AccessibleStateSet getAccessibleStateSet() {
            AccessibleStateSet states = super.getAccessibleStateSet();
            states.add(AccessibleState.SINGLE_LINE);
            return states;
        }
    }
}