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

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


	/**
	* Used to display a "Tip" for a Component. Typically components provide api
	* to automate the process of using <code>ToolTip</code>s.
	* For example, any Swing component can use the <code>JComponent</code>
	* <code>setToolTipText</code> method to specify the text
	* for a standard tooltip. A component that wants to create a custom
	* <code>ToolTip</code>
	* display can override <code>JComponent</code>'s <code>createToolTip</code>
	* method and use a subclass of this class.
	* <p>
	* See <a href="https://docs.oracle.com/javase/tutorial/uiswing/components/tooltip.html">How to Use Tool Tips</a>
	* in <em>The Java Tutorial</em>
	* for further documentation.
	* <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}.
	*
	* @see JComponent#setToolTipText
	* @see JComponent#createToolTip
	* @author Dave Moore
	* @author Rich Shiavi
	*/
	@SuppressWarnings("serial")
	public class JToolTip extends JComponent implements Accessible {
	/**
	* @see #getUIClassID
	* @see #readObject
	*/
	private static final String uiClassID = "ToolTipUI";

	String tipText;
	JComponent component;

	/** Creates a tool tip. */
	public JToolTip() {
	setOpaque(true);
	updateUI();
	}

	/**
	* Returns the L&F object that renders this component.
	*
	* @return the <code>ToolTipUI</code> object that renders this component
	*/
	public ToolTipUI getUI() {
	return (ToolTipUI)ui;
	}

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


	/**
	* Returns the name of the L&F class that renders this component.
	*
	* @return the string "ToolTipUI"
	* @see JComponent#getUIClassID
	* @see UIDefaults#getUI
	*/
	public String getUIClassID() {
	return uiClassID;
	}


	/**
	* Sets the text to show when the tool tip is displayed.
	* The string <code>tipText</code> may be <code>null</code>.
	*
	* @param tipText the <code>String</code> to display
	* @beaninfo
	* preferred: true
	* bound: true
	* description: Sets the text of the tooltip
	*/
	public void setTipText(String tipText) {
	String oldValue = this.tipText;
	this.tipText = tipText;
	firePropertyChange("tiptext", oldValue, tipText);

	if (!Objects.equals(oldValue, tipText)) {
	revalidate();
	repaint();
	}
	}

	/**
	* Returns the text that is shown when the tool tip is displayed.
	* The returned value may be <code>null</code>.
	*
	* @return the <code>String</code> that is displayed
	*/
	public String getTipText() {
	return tipText;
	}

	/**
	* Specifies the component that the tooltip describes.
	* The component <code>c</code> may be <code>null</code>
	* and will have no effect.
	* <p>
	* This is a bound property.
	*
	* @param c the <code>JComponent</code> being described
	* @see JComponent#createToolTip
	* @beaninfo
	* bound: true
	* description: Sets the component that the tooltip describes.
	*/
	public void setComponent(JComponent c) {
	JComponent oldValue = this.component;

	component = c;
	firePropertyChange("component", oldValue, c);
	}

	/**
	* Returns the component the tooltip applies to.
	* The returned value may be <code>null</code>.
	*
	* @return the component that the tooltip describes
	*
	* @see JComponent#createToolTip
	*/
	public JComponent getComponent() {
	return component;
	}

	/**
	* Always returns true since tooltips, by definition,
	* should always be on top of all other windows.
	*/
	// package private
	boolean alwaysOnTop() {
	return true;
	}


	/**
	* 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 <code>JToolTip</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>JToolTip</code>
	*/
	protected String paramString() {
	String tipTextString = (tipText != null ?
	tipText : "");

	return super.paramString() +
	",tipText=" + tipTextString;
	}


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

	/**
	* Gets the AccessibleContext associated with this JToolTip.
	* For tool tips, the AccessibleContext takes the form of an
	* AccessibleJToolTip.
	* A new AccessibleJToolTip instance is created if necessary.
	*
	* @return an AccessibleJToolTip that serves as the
	* AccessibleContext of this JToolTip
	*/
	public AccessibleContext getAccessibleContext() {
	if (accessibleContext == null) {
	accessibleContext = new AccessibleJToolTip();
	}
	return accessibleContext;
	}

	/**
	* This class implements accessibility support for the
	* <code>JToolTip</code> class. It provides an implementation of the
	* Java Accessibility API appropriate to tool tip 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 AccessibleJToolTip extends AccessibleJComponent {

	/**
	* Get the accessible description of this object.
	*
	* @return a localized String describing this object.
	*/
	public String getAccessibleDescription() {
	String description = accessibleDescription;

	// fallback to client property
	if (description == null) {
	description = (String)getClientProperty(AccessibleContext.ACCESSIBLE_DESCRIPTION_PROPERTY);
	}
	if (description == null) {
	description = getTipText();
	}
	return description;
	}

	/**
	* Get the role of this object.
	*
	* @return an instance of AccessibleRole describing the role of the
	* object
	*/
	public AccessibleRole getAccessibleRole() {
	return AccessibleRole.TOOL_TIP;
	}
	}
	}

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