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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
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package javax.swing;

	import java.beans.ConstructorProperties;

	import java.awt.*;
	import java.awt.event.*;
	import java.awt.image.*;

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

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


	/**
	* An implementation of a "push" button.
	* <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>
	* 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 information and examples of using buttons.
	* <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™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*
	* @beaninfo
	* attribute: isContainer false
	* description: An implementation of a \"push\" button.
	*
	* @author Jeff Dinkins
	*/
	@SuppressWarnings("serial")
	public class JButton extends AbstractButton implements Accessible {

	/**
	* @see #getUIClassID
	* @see #readObject
	*/
	private static final String uiClassID = "ButtonUI";

	/**
	* Creates a button with no set text or icon.
	*/
	public JButton() {
	this(null, null);
	}

	/**
	* Creates a button with an icon.
	*
	* @param icon the Icon image to display on the button
	*/
	public JButton(Icon icon) {
	this(null, icon);
	}

	/**
	* Creates a button with text.
	*
	* @param text the text of the button
	*/
	@ConstructorProperties({"text"})
	public JButton(String text) {
	this(text, null);
	}

	/**
	* Creates a button where properties are taken from the
	* <code>Action</code> supplied.
	*
	* @param a the <code>Action</code> used to specify the new button
	*
	* @since 1.3
	*/
	public JButton(Action a) {
	this();
	setAction(a);
	}

	/**
	* Creates a button with initial text and an icon.
	*
	* @param text the text of the button
	* @param icon the Icon image to display on the button
	*/
	public JButton(String text, Icon icon) {
	// Create the model
	setModel(new DefaultButtonModel());

	// initialize
	init(text, icon);
	}

	/**
	* 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.
	*
	* @return the string "ButtonUI"
	* @see JComponent#getUIClassID
	* @see UIDefaults#getUI
	* @beaninfo
	* expert: true
	* description: A string that specifies the name of the L&F class.
	*/
	public String getUIClassID() {
	return uiClassID;
	}


	/**
	* Gets the value of the <code>defaultButton</code> property,
	* which if <code>true</code> means that this button is the current
	* default button for its <code>JRootPane</code>.
	* Most look and feels render the default button
	* differently, and may potentially provide bindings
	* to access the default button.
	*
	* @return the value of the <code>defaultButton</code> property
	* @see JRootPane#setDefaultButton
	* @see #isDefaultCapable
	* @beaninfo
	* description: Whether or not this button is the default button
	*/
	public boolean isDefaultButton() {
	JRootPane root = SwingUtilities.getRootPane(this);
	if (root != null) {
	return root.getDefaultButton() == this;
	}
	return false;
	}

	/**
	* Gets the value of the <code>defaultCapable</code> property.
	*
	* @return the value of the <code>defaultCapable</code> property
	* @see #setDefaultCapable
	* @see #isDefaultButton
	* @see JRootPane#setDefaultButton
	*/
	public boolean isDefaultCapable() {
	return defaultCapable;
	}

	/**
	* Sets the <code>defaultCapable</code> property,
	* which determines whether this button can be
	* made the default button for its root pane.
	* The default value of the <code>defaultCapable</code>
	* property is <code>true</code> unless otherwise
	* specified by the look and feel.
	*
	* @param defaultCapable <code>true</code> if this button will be
	* capable of being the default button on the
	* <code>RootPane</code>; otherwise <code>false</code>
	* @see #isDefaultCapable
	* @beaninfo
	* bound: true
	* attribute: visualUpdate true
	* description: Whether or not this button can be the default button
	*/
	public void setDefaultCapable(boolean defaultCapable) {
	boolean oldDefaultCapable = this.defaultCapable;
	this.defaultCapable = defaultCapable;
	firePropertyChange("defaultCapable", oldDefaultCapable, defaultCapable);
	}

	/**
	* Overrides <code>JComponent.removeNotify</code> to check if
	* this button is currently set as the default button on the
	* <code>RootPane</code>, and if so, sets the <code>RootPane</code>'s
	* default button to <code>null</code> to ensure the
	* <code>RootPane</code> doesn't hold onto an invalid button reference.
	*/
	public void removeNotify() {
	JRootPane root = SwingUtilities.getRootPane(this);
	if (root != null && root.getDefaultButton() == this) {
	root.setDefaultButton(null);
	}
	super.removeNotify();
	}

	/**
	* 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);
	}
	}
	}


	/**
	* Returns a string representation of this <code>JButton</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>JButton</code>
	*/
	protected String paramString() {
	String defaultCapableString = (defaultCapable ? "true" : "false");

	return super.paramString() +
	",defaultCapable=" + defaultCapableString;
	}


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

	/**
	* Gets the <code>AccessibleContext</code> associated with this
	* <code>JButton</code>. For <code>JButton</code>s,
	* the <code>AccessibleContext</code> takes the form of an
	* <code>AccessibleJButton</code>.
	* A new <code>AccessibleJButton</code> instance is created if necessary.
	*
	* @return an <code>AccessibleJButton</code> that serves as the
	* <code>AccessibleContext</code> of this <code>JButton</code>
	* @beaninfo
	* expert: true
	* description: The AccessibleContext associated with this Button.
	*/
	public AccessibleContext getAccessibleContext() {
	if (accessibleContext == null) {
	accessibleContext = new AccessibleJButton();
	}
	return accessibleContext;
	}

	/**
	* This class implements accessibility support for the
	* <code>JButton</code> class. It provides an implementation of the
	* Java Accessibility API appropriate to button 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™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*/
	@SuppressWarnings("serial")
	protected class AccessibleJButton extends AccessibleAbstractButton {

	/**
	* Get the role of this object.
	*
	* @return an instance of AccessibleRole describing the role of the
	* object
	* @see AccessibleRole
	*/
	public AccessibleRole getAccessibleRole() {
	return AccessibleRole.PUSH_BUTTON;
	}
	} // inner class AccessibleJButton
	}

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