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/*
 * Copyright (c) 1997, 2013, 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
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package javax.swing;

import java.awt.*;
import java.awt.event.*;
import java.beans.*;

import javax.swing.plaf.*;
import javax.accessibility.*;

import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;



An implementation of a check box -- an item that can be selected or
deselected, and which displays its state to the user.
By convention, any number of check boxes in a group can be selected.
See How to Use Buttons, Check Boxes, and Radio Buttons
in The Java Tutorial
for examples and information on using check boxes.


Buttons can be configured, and to some degree controlled, by
Actions.  Using an
Action with a button has many benefits beyond directly
configuring a button.  Refer to 
Swing Components Supporting Action for more
details, and you can find more information in How
to Use Actions, a section in The Java Tutorial.


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:Jeff Dinkins
See Also:
@beaninfo
  attribute: isContainer false
description: A component which can be selected or deselected.
/**
 * An implementation of a check box -- an item that can be selected or
 * deselected, and which displays its state to the user.
 * By convention, any number of check boxes in a group can be selected.
 * See <a href="https://docs.oracle.com/javase/tutorial/uiswing/components/button.html">How to Use Buttons, Check Boxes, and Radio Buttons</a>
 * in <em>The Java Tutorial</em>
 * for examples and information on using check boxes.
 * <p>
 * Buttons can be configured, and to some degree controlled, by
 * <code><a href="Action.html">Action</a></code>s.  Using an
 * <code>Action</code> with a button has many benefits beyond directly
 * configuring a button.  Refer to <a href="Action.html#buttonActions">
 * Swing Components Supporting <code>Action</code></a> for more
 * details, and you can find more information in <a
 * href="https://docs.oracle.com/javase/tutorial/uiswing/misc/action.html">How
 * to Use Actions</a>, a section in <em>The Java Tutorial</em>.
 * <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}.
 *
 * @see JRadioButton
 *
 * @beaninfo
 *   attribute: isContainer false
 * description: A component which can be selected or deselected.
 *
 * @author Jeff Dinkins
 */
public class JCheckBox extends JToggleButton implements Accessible {

    
Identifies a change to the flat property. 
/** Identifies a change to the flat property. */
    public static final String BORDER_PAINTED_FLAT_CHANGED_PROPERTY = "borderPaintedFlat";

    private boolean flat = false;

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


    
Creates an initially unselected check box button with no text, no icon.

/**
     * Creates an initially unselected check box button with no text, no icon.
     */
    public JCheckBox () {
        this(null, null, false);
    }

    
Creates an initially unselected check box with an icon.

Params:
  • icon –  the Icon image to display
/**
     * Creates an initially unselected check box with an icon.
     *
     * @param icon  the Icon image to display
     */
    public JCheckBox(Icon icon) {
        this(null, icon, false);
    }

    
Creates a check box with an icon and specifies whether
or not it is initially selected.

Params:
  • icon –  the Icon image to display
  • selected – a boolean value indicating the initial selection
       state. If true the check box is selected
/**
     * Creates a check box with an icon and specifies whether
     * or not it is initially selected.
     *
     * @param icon  the Icon image to display
     * @param selected a boolean value indicating the initial selection
     *        state. If <code>true</code> the check box is selected
     */
    public JCheckBox(Icon icon, boolean selected) {
        this(null, icon, selected);
    }

    
Creates an initially unselected check box with text.

Params:
  • text – the text of the check box.
/**
     * Creates an initially unselected check box with text.
     *
     * @param text the text of the check box.
     */
    public JCheckBox (String text) {
        this(text, null, false);
    }

    
Creates a check box where properties are taken from the
Action supplied.

Since:1.3
/**
     * Creates a check box where properties are taken from the
     * Action supplied.
     *
     * @since 1.3
     */
    public JCheckBox(Action a) {
        this();
        setAction(a);
    }


    
Creates a check box with text and specifies whether
or not it is initially selected.

Params:
  • text – the text of the check box.
  • selected – a boolean value indicating the initial selection
       state. If true the check box is selected
/**
     * Creates a check box with text and specifies whether
     * or not it is initially selected.
     *
     * @param text the text of the check box.
     * @param selected a boolean value indicating the initial selection
     *        state. If <code>true</code> the check box is selected
     */
    public JCheckBox (String text, boolean selected) {
        this(text, null, selected);
    }

    
Creates an initially unselected check box with
the specified text and icon.

Params:
  • text – the text of the check box.
  • icon –  the Icon image to display
/**
     * Creates an initially unselected check box with
     * the specified text and icon.
     *
     * @param text the text of the check box.
     * @param icon  the Icon image to display
     */
    public JCheckBox(String text, Icon icon) {
        this(text, icon, false);
    }

    
Creates a check box with text and icon,
and specifies whether or not it is initially selected.

Params:
  • text – the text of the check box.
  • icon –  the Icon image to display
  • selected – a boolean value indicating the initial selection
       state. If true the check box is selected
/**
     * Creates a check box with text and icon,
     * and specifies whether or not it is initially selected.
     *
     * @param text the text of the check box.
     * @param icon  the Icon image to display
     * @param selected a boolean value indicating the initial selection
     *        state. If <code>true</code> the check box is selected
     */
    public JCheckBox (String text, Icon icon, boolean selected) {
        super(text, icon, selected);
        setUIProperty("borderPainted", Boolean.FALSE);
        setHorizontalAlignment(LEADING);
    }

    
Sets the borderPaintedFlat property,
which gives a hint to the look and feel as to the
appearance of the check box border.
This is usually set to true when a
JCheckBox instance is used as a
renderer in a component such as a JTable or
JTree.  The default value for the
borderPaintedFlat property is false.
This method fires a property changed event.
Some look and feels might not implement flat borders;
they will ignore this property.

Params:
  • b – true requests that the border be painted flat;
         false requests normal borders
See Also:
@beaninfo
       bound: true
   attribute: visualUpdate true
 description: Whether the border is painted flat.
Since:1.3
/**
     * Sets the <code>borderPaintedFlat</code> property,
     * which gives a hint to the look and feel as to the
     * appearance of the check box border.
     * This is usually set to <code>true</code> when a
     * <code>JCheckBox</code> instance is used as a
     * renderer in a component such as a <code>JTable</code> or
     * <code>JTree</code>.  The default value for the
     * <code>borderPaintedFlat</code> property is <code>false</code>.
     * This method fires a property changed event.
     * Some look and feels might not implement flat borders;
     * they will ignore this property.
     *
     * @param b <code>true</code> requests that the border be painted flat;
     *          <code>false</code> requests normal borders
     * @see #isBorderPaintedFlat
     * @beaninfo
     *        bound: true
     *    attribute: visualUpdate true
     *  description: Whether the border is painted flat.
     * @since 1.3
     */
    public void setBorderPaintedFlat(boolean b) {
        boolean oldValue = flat;
        flat = b;
        firePropertyChange(BORDER_PAINTED_FLAT_CHANGED_PROPERTY, oldValue, flat);
        if (b != oldValue) {
            revalidate();
            repaint();
        }
    }

    
Gets the value of the borderPaintedFlat property.

See Also:
Returns:the value of the borderPaintedFlat property
Since:1.3
/**
     * Gets the value of the <code>borderPaintedFlat</code> property.
     *
     * @return the value of the <code>borderPaintedFlat</code> property
     * @see #setBorderPaintedFlat
     * @since 1.3
     */
    public boolean isBorderPaintedFlat() {
        return flat;
    }

    
Resets the UI property to a value from the current look and feel.

See Also:
  • updateUI.updateUI
/**
     * Resets the UI property to a value from the current look and feel.
     *
     * @see JComponent#updateUI
     */
    public void updateUI() {
        setUI((ButtonUI)UIManager.getUI(this));
    }


    
Returns a string that specifies the name of the L&F class
that renders this component.

See Also:
Returns:the string "CheckBoxUI"
@beaninfo
       expert: true
  description: A string that specifies the name of the L&F class
/**
     * Returns a string that specifies the name of the L&amp;F class
     * that renders this component.
     *
     * @return the string "CheckBoxUI"
     * @see JComponent#getUIClassID
     * @see UIDefaults#getUI
     * @beaninfo
     *        expert: true
     *   description: A string that specifies the name of the L&amp;F class
     */
    public String getUIClassID() {
        return uiClassID;
    }


    
The icon for checkboxs comes from the look and feel,
not the Action; this is overriden to do nothing.

/**
     * The icon for checkboxs comes from the look and feel,
     * not the Action; this is overriden to do nothing.
     */
    void setIconFromAction(Action a) {
    }

     /*
      * See readObject and writeObject in JComponent 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);
            }
        }
     }


    
See JComponent.readObject() for information about serialization
in Swing.

/**
     * See JComponent.readObject() for information about serialization
     * in Swing.
     */
    private void readObject(ObjectInputStream s)
        throws IOException, ClassNotFoundException
    {
        s.defaultReadObject();
        if (getUIClassID().equals(uiClassID)) {
            updateUI();
        }
    }


    
Returns a string representation of this JCheckBox. 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.
specific new aspects of the JFC components.

Returns: a string representation of this JCheckBox.
/**
     * Returns a string representation of this JCheckBox. 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>.
     * specific new aspects of the JFC components.
     *
     * @return  a string representation of this JCheckBox.
     */
    protected String paramString() {
        return super.paramString();
    }

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

    
Gets the AccessibleContext associated with this JCheckBox.
For JCheckBoxes, the AccessibleContext takes the form of an
AccessibleJCheckBox.
A new AccessibleJCheckBox instance is created if necessary.

Returns:an AccessibleJCheckBox that serves as the
        AccessibleContext of this JCheckBox
@beaninfo
      expert: true
 description: The AccessibleContext associated with this CheckBox.
/**
     * Gets the AccessibleContext associated with this JCheckBox.
     * For JCheckBoxes, the AccessibleContext takes the form of an
     * AccessibleJCheckBox.
     * A new AccessibleJCheckBox instance is created if necessary.
     *
     * @return an AccessibleJCheckBox that serves as the
     *         AccessibleContext of this JCheckBox
     * @beaninfo
     *       expert: true
     *  description: The AccessibleContext associated with this CheckBox.
     */
    public AccessibleContext getAccessibleContext() {
        if (accessibleContext == null) {
            accessibleContext = new AccessibleJCheckBox();
        }
        return accessibleContext;
    }

    
This class implements accessibility support for the
JCheckBox class.  It provides an implementation of the
Java Accessibility API appropriate to check box 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>JCheckBox</code> class.  It provides an implementation of the
     * Java Accessibility API appropriate to check box 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}.
     */
    protected class AccessibleJCheckBox extends AccessibleJToggleButton {

        
Get the role of this object.

See Also:
Returns:an instance of AccessibleRole describing the role of the object
/**
         * Get the role of this object.
         *
         * @return an instance of AccessibleRole describing the role of the object
         * @see AccessibleRole
         */
        public AccessibleRole getAccessibleRole() {
            return AccessibleRole.CHECK_BOX;
        }

    } // inner class AccessibleJCheckBox
}