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	/*
	* Copyright (c) 1995, 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 java.awt;

	import java.awt.peer.ScrollbarPeer;
	import java.awt.event.*;
	import java.util.EventListener;
	import java.io.ObjectOutputStream;
	import java.io.ObjectInputStream;
	import java.io.IOException;
	import javax.accessibility.*;


	/**
	* The <code>Scrollbar</code> class embodies a scroll bar, a
	* familiar user-interface object. A scroll bar provides a
	* convenient means for allowing a user to select from a
	* range of values. The following three vertical
	* scroll bars could be used as slider controls to pick
	* the red, green, and blue components of a color:
	* <p>
	* <img src="doc-files/Scrollbar-1.gif" alt="Image shows 3 vertical sliders, side-by-side."
	* style="float:center; margin: 7px 10px;">
	* <p>
	* Each scroll bar in this example could be created with
	* code similar to the following:
	*
	* <hr><blockquote><pre>
	* redSlider=new Scrollbar(Scrollbar.VERTICAL, 0, 1, 0, 255);
	* add(redSlider);
	* </pre></blockquote><hr>
	* <p>
	* Alternatively, a scroll bar can represent a range of values. For
	* example, if a scroll bar is used for scrolling through text, the
	* width of the "bubble" (also called the "thumb" or "scroll box")
	* can be used to represent the amount of text that is visible.
	* Here is an example of a scroll bar that represents a range:
	* <p>
	* <img src="doc-files/Scrollbar-2.gif"
	* alt="Image shows horizontal slider with starting range of 0 and ending range of 300. The slider thumb is labeled 60."
	* style="float:center; margin: 7px 10px;">
	* <p>
	* The value range represented by the bubble in this example
	* is the <em>visible amount</em>. The horizontal scroll bar
	* in this example could be created with code like the following:
	*
	* <hr><blockquote><pre>
	* ranger = new Scrollbar(Scrollbar.HORIZONTAL, 0, 60, 0, 300);
	* add(ranger);
	* </pre></blockquote><hr>
	* <p>
	* Note that the actual maximum value of the scroll bar is the
	* <code>maximum</code> minus the <code>visible amount</code>.
	* In the previous example, because the <code>maximum</code> is
	* 300 and the <code>visible amount</code> is 60, the actual maximum
	* value is 240. The range of the scrollbar track is 0 - 300.
	* The left side of the bubble indicates the value of the
	* scroll bar.
	* <p>
	* Normally, the user changes the value of the scroll bar by
	* making a gesture with the mouse. For example, the user can
	* drag the scroll bar's bubble up and down, or click in the
	* scroll bar's unit increment or block increment areas. Keyboard
	* gestures can also be mapped to the scroll bar. By convention,
	* the <b>Page Up</b> and <b>Page Down</b>
	* keys are equivalent to clicking in the scroll bar's block
	* increment and block decrement areas.
	* <p>
	* When the user changes the value of the scroll bar, the scroll bar
	* receives an instance of <code>AdjustmentEvent</code>.
	* The scroll bar processes this event, passing it along to
	* any registered listeners.
	* <p>
	* Any object that wishes to be notified of changes to the
	* scroll bar's value should implement
	* <code>AdjustmentListener</code>, an interface defined in
	* the package <code>java.awt.event</code>.
	* Listeners can be added and removed dynamically by calling
	* the methods <code>addAdjustmentListener</code> and
	* <code>removeAdjustmentListener</code>.
	* <p>
	* The <code>AdjustmentEvent</code> class defines five types
	* of adjustment event, listed here:
	*
	* <ul>
	* <li><code>AdjustmentEvent.TRACK</code> is sent out when the
	* user drags the scroll bar's bubble.
	* <li><code>AdjustmentEvent.UNIT_INCREMENT</code> is sent out
	* when the user clicks in the left arrow of a horizontal scroll
	* bar, or the top arrow of a vertical scroll bar, or makes the
	* equivalent gesture from the keyboard.
	* <li><code>AdjustmentEvent.UNIT_DECREMENT</code> is sent out
	* when the user clicks in the right arrow of a horizontal scroll
	* bar, or the bottom arrow of a vertical scroll bar, or makes the
	* equivalent gesture from the keyboard.
	* <li><code>AdjustmentEvent.BLOCK_INCREMENT</code> is sent out
	* when the user clicks in the track, to the left of the bubble
	* on a horizontal scroll bar, or above the bubble on a vertical
	* scroll bar. By convention, the <b>Page Up</b>
	* key is equivalent, if the user is using a keyboard that
	* defines a <b>Page Up</b> key.
	* <li><code>AdjustmentEvent.BLOCK_DECREMENT</code> is sent out
	* when the user clicks in the track, to the right of the bubble
	* on a horizontal scroll bar, or below the bubble on a vertical
	* scroll bar. By convention, the <b>Page Down</b>
	* key is equivalent, if the user is using a keyboard that
	* defines a <b>Page Down</b> key.
	* </ul>
	* <p>
	* The JDK 1.0 event system is supported for backwards
	* compatibility, but its use with newer versions of the platform is
	* discouraged. The five types of adjustment events introduced
	* with JDK 1.1 correspond to the five event types
	* that are associated with scroll bars in previous platform versions.
	* The following list gives the adjustment event type,
	* and the corresponding JDK 1.0 event type it replaces.
	*
	* <ul>
	* <li><code>AdjustmentEvent.TRACK</code> replaces
	* <code>Event.SCROLL_ABSOLUTE</code>
	* <li><code>AdjustmentEvent.UNIT_INCREMENT</code> replaces
	* <code>Event.SCROLL_LINE_UP</code>
	* <li><code>AdjustmentEvent.UNIT_DECREMENT</code> replaces
	* <code>Event.SCROLL_LINE_DOWN</code>
	* <li><code>AdjustmentEvent.BLOCK_INCREMENT</code> replaces
	* <code>Event.SCROLL_PAGE_UP</code>
	* <li><code>AdjustmentEvent.BLOCK_DECREMENT</code> replaces
	* <code>Event.SCROLL_PAGE_DOWN</code>
	* </ul>
	* <p>
	* <b>Note</b>: We recommend using a <code>Scrollbar</code>
	* for value selection only. If you want to implement
	* a scrollable component inside a container, we recommend you use
	* a {@link ScrollPane ScrollPane}. If you use a
	* <code>Scrollbar</code> for this purpose, you are likely to
	* encounter issues with painting, key handling, sizing and
	* positioning.
	*
	* @author Sami Shaio
	* @see java.awt.event.AdjustmentEvent
	* @see java.awt.event.AdjustmentListener
	* @since JDK1.0
	*/
	public class Scrollbar extends Component implements Adjustable, Accessible {

	/**
	* A constant that indicates a horizontal scroll bar.
	*/
	public static final int HORIZONTAL = 0;

	/**
	* A constant that indicates a vertical scroll bar.
	*/
	public static final int VERTICAL = 1;

	/**
	* The value of the <code>Scrollbar</code>.
	* This property must be greater than or equal to <code>minimum</code>
	* and less than or equal to
	* <code>maximum - visibleAmount</code>
	*
	* @serial
	* @see #getValue
	* @see #setValue
	*/
	int value;

	/**
	* The maximum value of the <code>Scrollbar</code>.
	* This value must be greater than the <code>minimum</code>
	* value.<br>
	*
	* @serial
	* @see #getMaximum
	* @see #setMaximum
	*/
	int maximum;

	/**
	* The minimum value of the <code>Scrollbar</code>.
	* This value must be less than the <code>maximum</code>
	* value.<br>
	*
	* @serial
	* @see #getMinimum
	* @see #setMinimum
	*/
	int minimum;

	/**
	* The size of the <code>Scrollbar</code>'s bubble.
	* When a scroll bar is used to select a range of values,
	* the visibleAmount represents the size of this range.
	* Depending on platform, this may be visually indicated
	* by the size of the bubble.
	*
	* @serial
	* @see #getVisibleAmount
	* @see #setVisibleAmount
	*/
	int visibleAmount;

	/**
	* The <code>Scrollbar</code>'s orientation--being either horizontal
	* or vertical.
	* This value should be specified when the scrollbar is created.<BR>
	* orientation can be either : <code>VERTICAL</code> or
	* <code>HORIZONTAL</code> only.
	*
	* @serial
	* @see #getOrientation
	* @see #setOrientation
	*/
	int orientation;

	/**
	* The amount by which the scrollbar value will change when going
	* up or down by a line.
	* This value must be greater than zero.
	*
	* @serial
	* @see #getLineIncrement
	* @see #setLineIncrement
	*/
	int lineIncrement = 1;

	/**
	* The amount by which the scrollbar value will change when going
	* up or down by a page.
	* This value must be greater than zero.
	*
	* @serial
	* @see #getPageIncrement
	* @see #setPageIncrement
	*/
	int pageIncrement = 10;

	/**
	* The adjusting status of the <code>Scrollbar</code>.
	* True if the value is in the process of changing as a result of
	* actions being taken by the user.
	*
	* @see #getValueIsAdjusting
	* @see #setValueIsAdjusting
	* @since 1.4
	*/
	transient boolean isAdjusting;

	transient AdjustmentListener adjustmentListener;

	private static final String base = "scrollbar";
	private static int nameCounter = 0;

	/*
	* JDK 1.1 serialVersionUID
	*/
	private static final long serialVersionUID = 8451667562882310543L;

	/**
	* Initialize JNI field and method IDs.
	*/
	private static native void initIDs();

	static {
	/* ensure that the necessary native libraries are loaded */
	Toolkit.loadLibraries();
	if (!GraphicsEnvironment.isHeadless()) {
	initIDs();
	}
	}

	/**
	* Constructs a new vertical scroll bar.
	* The default properties of the scroll bar are listed in
	* the following table:
	*
	* <table border=1 summary="Scrollbar default properties">
	* <tr>
	* <th>Property</th>
	* <th>Description</th>
	* <th>Default Value</th>
	* </tr>
	* <tr>
	* <td>orientation</td>
	* <td>indicates whether the scroll bar is vertical
	* <br>or horizontal</td>
	* <td><code>Scrollbar.VERTICAL</code></td>
	* </tr>
	* <tr>
	* <td>value</td>
	* <td>value which controls the location
	* <br>of the scroll bar's bubble</td>
	* <td>0</td>
	* </tr>
	* <tr>
	* <td>visible amount</td>
	* <td>visible amount of the scroll bar's range,
	* <br>typically represented by the size of the
	* <br>scroll bar's bubble</td>
	* <td>10</td>
	* </tr>
	* <tr>
	* <td>minimum</td>
	* <td>minimum value of the scroll bar</td>
	* <td>0</td>
	* </tr>
	* <tr>
	* <td>maximum</td>
	* <td>maximum value of the scroll bar</td>
	* <td>100</td>
	* </tr>
	* <tr>
	* <td>unit increment</td>
	* <td>amount the value changes when the
	* <br>Line Up or Line Down key is pressed,
	* <br>or when the end arrows of the scrollbar
	* <br>are clicked </td>
	* <td>1</td>
	* </tr>
	* <tr>
	* <td>block increment</td>
	* <td>amount the value changes when the
	* <br>Page Up or Page Down key is pressed,
	* <br>or when the scrollbar track is clicked
	* <br>on either side of the bubble </td>
	* <td>10</td>
	* </tr>
	* </table>
	*
	* @exception HeadlessException if GraphicsEnvironment.isHeadless()
	* returns true.
	* @see java.awt.GraphicsEnvironment#isHeadless
	*/
	public Scrollbar() throws HeadlessException {
	this(VERTICAL, 0, 10, 0, 100);
	}

	/**
	* Constructs a new scroll bar with the specified orientation.
	* <p>
	* The <code>orientation</code> argument must take one of the two
	* values <code>Scrollbar.HORIZONTAL</code>,
	* or <code>Scrollbar.VERTICAL</code>,
	* indicating a horizontal or vertical scroll bar, respectively.
	*
	* @param orientation indicates the orientation of the scroll bar
	* @exception IllegalArgumentException when an illegal value for
	* the <code>orientation</code> argument is supplied
	* @exception HeadlessException if GraphicsEnvironment.isHeadless()
	* returns true.
	* @see java.awt.GraphicsEnvironment#isHeadless
	*/
	public Scrollbar(int orientation) throws HeadlessException {
	this(orientation, 0, 10, 0, 100);
	}

	/**
	* Constructs a new scroll bar with the specified orientation,
	* initial value, visible amount, and minimum and maximum values.
	* <p>
	* The <code>orientation</code> argument must take one of the two
	* values <code>Scrollbar.HORIZONTAL</code>,
	* or <code>Scrollbar.VERTICAL</code>,
	* indicating a horizontal or vertical scroll bar, respectively.
	* <p>
	* The parameters supplied to this constructor are subject to the
	* constraints described in {@link #setValues(int, int, int, int)}.
	*
	* @param orientation indicates the orientation of the scroll bar.
	* @param value the initial value of the scroll bar
	* @param visible the visible amount of the scroll bar, typically
	* represented by the size of the bubble
	* @param minimum the minimum value of the scroll bar
	* @param maximum the maximum value of the scroll bar
	* @exception IllegalArgumentException when an illegal value for
	* the <code>orientation</code> argument is supplied
	* @exception HeadlessException if GraphicsEnvironment.isHeadless()
	* returns true.
	* @see #setValues
	* @see java.awt.GraphicsEnvironment#isHeadless
	*/
	public Scrollbar(int orientation, int value, int visible, int minimum,
	int maximum) throws HeadlessException {
	GraphicsEnvironment.checkHeadless();
	switch (orientation) {
	case HORIZONTAL:
	case VERTICAL:
	this.orientation = orientation;
	break;
	default:
	throw new IllegalArgumentException("illegal scrollbar orientation");
	}
	setValues(value, visible, minimum, maximum);
	}

	/**
	* Constructs a name for this component. Called by <code>getName</code>
	* when the name is <code>null</code>.
	*/
	String constructComponentName() {
	synchronized (Scrollbar.class) {
	return base + nameCounter++;
	}
	}

	/**
	* Creates the <code>Scrollbar</code>'s peer. The peer allows you to modify
	* the appearance of the <code>Scrollbar</code> without changing any of its
	* functionality.
	*/
	public void addNotify() {
	synchronized (getTreeLock()) {
	if (peer == null)
	peer = getToolkit().createScrollbar(this);
	super.addNotify();
	}
	}

	/**
	* Returns the orientation of this scroll bar.
	*
	* @return the orientation of this scroll bar, either
	* <code>Scrollbar.HORIZONTAL</code> or
	* <code>Scrollbar.VERTICAL</code>
	* @see java.awt.Scrollbar#setOrientation
	*/
	public int getOrientation() {
	return orientation;
	}

	/**
	* Sets the orientation for this scroll bar.
	*
	* @param orientation the orientation of this scroll bar, either
	* <code>Scrollbar.HORIZONTAL</code> or
	* <code>Scrollbar.VERTICAL</code>
	* @see java.awt.Scrollbar#getOrientation
	* @exception IllegalArgumentException if the value supplied
	* for <code>orientation</code> is not a
	* legal value
	* @since JDK1.1
	*/
	public void setOrientation(int orientation) {
	synchronized (getTreeLock()) {
	if (orientation == this.orientation) {
	return;
	}
	switch (orientation) {
	case HORIZONTAL:
	case VERTICAL:
	this.orientation = orientation;
	break;
	default:
	throw new IllegalArgumentException("illegal scrollbar orientation");
	}
	/* Create a new peer with the specified orientation. */
	if (peer != null) {
	removeNotify();
	addNotify();
	invalidate();
	}
	}
	if (accessibleContext != null) {
	accessibleContext.firePropertyChange(
	AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
	((orientation == VERTICAL)
	? AccessibleState.HORIZONTAL : AccessibleState.VERTICAL),
	((orientation == VERTICAL)
	? AccessibleState.VERTICAL : AccessibleState.HORIZONTAL));
	}
	}

	/**
	* Gets the current value of this scroll bar.
	*
	* @return the current value of this scroll bar
	* @see java.awt.Scrollbar#getMinimum
	* @see java.awt.Scrollbar#getMaximum
	*/
	public int getValue() {
	return value;
	}

	/**
	* Sets the value of this scroll bar to the specified value.
	* <p>
	* If the value supplied is less than the current <code>minimum</code>
	* or greater than the current <code>maximum - visibleAmount</code>,
	* then either <code>minimum</code> or <code>maximum - visibleAmount</code>
	* is substituted, as appropriate.
	* <p>
	* Normally, a program should change a scroll bar's
	* value only by calling <code>setValues</code>.
	* The <code>setValues</code> method simultaneously
	* and synchronously sets the minimum, maximum, visible amount,
	* and value properties of a scroll bar, so that they are
	* mutually consistent.
	* <p>
	* Calling this method does not fire an
	* <code>AdjustmentEvent</code>.
	*
	* @param newValue the new value of the scroll bar
	* @see java.awt.Scrollbar#setValues
	* @see java.awt.Scrollbar#getValue
	* @see java.awt.Scrollbar#getMinimum
	* @see java.awt.Scrollbar#getMaximum
	*/
	public void setValue(int newValue) {
	// Use setValues so that a consistent policy relating
	// minimum, maximum, visible amount, and value is enforced.
	setValues(newValue, visibleAmount, minimum, maximum);
	}

	/**
	* Gets the minimum value of this scroll bar.
	*
	* @return the minimum value of this scroll bar
	* @see java.awt.Scrollbar#getValue
	* @see java.awt.Scrollbar#getMaximum
	*/
	public int getMinimum() {
	return minimum;
	}

	/**
	* Sets the minimum value of this scroll bar.
	* <p>
	* When <code>setMinimum</code> is called, the minimum value
	* is changed, and other values (including the maximum, the
	* visible amount, and the current scroll bar value)
	* are changed to be consistent with the new minimum.
	* <p>
	* Normally, a program should change a scroll bar's minimum
	* value only by calling <code>setValues</code>.
	* The <code>setValues</code> method simultaneously
	* and synchronously sets the minimum, maximum, visible amount,
	* and value properties of a scroll bar, so that they are
	* mutually consistent.
	* <p>
	* Note that setting the minimum value to <code>Integer.MAX_VALUE</code>
	* will result in the new minimum value being set to
	* <code>Integer.MAX_VALUE - 1</code>.
	*
	* @param newMinimum the new minimum value for this scroll bar
	* @see java.awt.Scrollbar#setValues
	* @see java.awt.Scrollbar#setMaximum
	* @since JDK1.1
	*/
	public void setMinimum(int newMinimum) {
	// No checks are necessary in this method since minimum is
	// the first variable checked in the setValues function.

	// Use setValues so that a consistent policy relating
	// minimum, maximum, visible amount, and value is enforced.
	setValues(value, visibleAmount, newMinimum, maximum);
	}

	/**
	* Gets the maximum value of this scroll bar.
	*
	* @return the maximum value of this scroll bar
	* @see java.awt.Scrollbar#getValue
	* @see java.awt.Scrollbar#getMinimum
	*/
	public int getMaximum() {
	return maximum;
	}

	/**
	* Sets the maximum value of this scroll bar.
	* <p>
	* When <code>setMaximum</code> is called, the maximum value
	* is changed, and other values (including the minimum, the
	* visible amount, and the current scroll bar value)
	* are changed to be consistent with the new maximum.
	* <p>
	* Normally, a program should change a scroll bar's maximum
	* value only by calling <code>setValues</code>.
	* The <code>setValues</code> method simultaneously
	* and synchronously sets the minimum, maximum, visible amount,
	* and value properties of a scroll bar, so that they are
	* mutually consistent.
	* <p>
	* Note that setting the maximum value to <code>Integer.MIN_VALUE</code>
	* will result in the new maximum value being set to
	* <code>Integer.MIN_VALUE + 1</code>.
	*
	* @param newMaximum the new maximum value
	* for this scroll bar
	* @see java.awt.Scrollbar#setValues
	* @see java.awt.Scrollbar#setMinimum
	* @since JDK1.1
	*/
	public void setMaximum(int newMaximum) {
	// minimum is checked first in setValues, so we need to
	// enforce minimum and maximum checks here.
	if (newMaximum == Integer.MIN_VALUE) {
	newMaximum = Integer.MIN_VALUE + 1;
	}

	if (minimum >= newMaximum) {
	minimum = newMaximum - 1;
	}

	// Use setValues so that a consistent policy relating
	// minimum, maximum, visible amount, and value is enforced.
	setValues(value, visibleAmount, minimum, newMaximum);
	}

	/**
	* Gets the visible amount of this scroll bar.
	* <p>
	* When a scroll bar is used to select a range of values,
	* the visible amount is used to represent the range of values
	* that are currently visible. The size of the scroll bar's
	* bubble (also called a thumb or scroll box), usually gives a
	* visual representation of the relationship of the visible
	* amount to the range of the scroll bar.
	* Note that depending on platform, the value of the visible amount property
	* may not be visually indicated by the size of the bubble.
	* <p>
	* The scroll bar's bubble may not be displayed when it is not
	* moveable (e.g. when it takes up the entire length of the
	* scroll bar's track, or when the scroll bar is disabled).
	* Whether the bubble is displayed or not will not affect
	* the value returned by <code>getVisibleAmount</code>.
	*
	* @return the visible amount of this scroll bar
	* @see java.awt.Scrollbar#setVisibleAmount
	* @since JDK1.1
	*/
	public int getVisibleAmount() {
	return getVisible();
	}

	/**
	* @deprecated As of JDK version 1.1,
	* replaced by <code>getVisibleAmount()</code>.
	*/
	@Deprecated
	public int getVisible() {
	return visibleAmount;
	}

	/**
	* Sets the visible amount of this scroll bar.
	* <p>
	* When a scroll bar is used to select a range of values,
	* the visible amount is used to represent the range of values
	* that are currently visible. The size of the scroll bar's
	* bubble (also called a thumb or scroll box), usually gives a
	* visual representation of the relationship of the visible
	* amount to the range of the scroll bar.
	* Note that depending on platform, the value of the visible amount property
	* may not be visually indicated by the size of the bubble.
	* <p>
	* The scroll bar's bubble may not be displayed when it is not
	* moveable (e.g. when it takes up the entire length of the
	* scroll bar's track, or when the scroll bar is disabled).
	* Whether the bubble is displayed or not will not affect
	* the value returned by <code>getVisibleAmount</code>.
	* <p>
	* If the visible amount supplied is less than <code>one</code>
	* or greater than the current <code>maximum - minimum</code>,
	* then either <code>one</code> or <code>maximum - minimum</code>
	* is substituted, as appropriate.
	* <p>
	* Normally, a program should change a scroll bar's
	* value only by calling <code>setValues</code>.
	* The <code>setValues</code> method simultaneously
	* and synchronously sets the minimum, maximum, visible amount,
	* and value properties of a scroll bar, so that they are
	* mutually consistent.
	*
	* @param newAmount the new visible amount
	* @see java.awt.Scrollbar#getVisibleAmount
	* @see java.awt.Scrollbar#setValues
	* @since JDK1.1
	*/
	public void setVisibleAmount(int newAmount) {
	// Use setValues so that a consistent policy relating
	// minimum, maximum, visible amount, and value is enforced.
	setValues(value, newAmount, minimum, maximum);
	}

	/**
	* Sets the unit increment for this scroll bar.
	* <p>
	* The unit increment is the value that is added or subtracted
	* when the user activates the unit increment area of the
	* scroll bar, generally through a mouse or keyboard gesture
	* that the scroll bar receives as an adjustment event.
	* The unit increment must be greater than zero.
	* Attepts to set the unit increment to a value lower than 1
	* will result in a value of 1 being set.
	* <p>
	* In some operating systems, this property
	* can be ignored by the underlying controls.
	*
	* @param v the amount by which to increment or decrement
	* the scroll bar's value
	* @see java.awt.Scrollbar#getUnitIncrement
	* @since JDK1.1
	*/
	public void setUnitIncrement(int v) {
	setLineIncrement(v);
	}

	/**
	* @deprecated As of JDK version 1.1,
	* replaced by <code>setUnitIncrement(int)</code>.
	*/
	@Deprecated
	public synchronized void setLineIncrement(int v) {
	int tmp = (v < 1) ? 1 : v;

	if (lineIncrement == tmp) {
	return;
	}
	lineIncrement = tmp;

	ScrollbarPeer peer = (ScrollbarPeer)this.peer;
	if (peer != null) {
	peer.setLineIncrement(lineIncrement);
	}
	}

	/**
	* Gets the unit increment for this scrollbar.
	* <p>
	* The unit increment is the value that is added or subtracted
	* when the user activates the unit increment area of the
	* scroll bar, generally through a mouse or keyboard gesture
	* that the scroll bar receives as an adjustment event.
	* The unit increment must be greater than zero.
	* <p>
	* In some operating systems, this property
	* can be ignored by the underlying controls.
	*
	* @return the unit increment of this scroll bar
	* @see java.awt.Scrollbar#setUnitIncrement
	* @since JDK1.1
	*/
	public int getUnitIncrement() {
	return getLineIncrement();
	}

	/**
	* @deprecated As of JDK version 1.1,
	* replaced by <code>getUnitIncrement()</code>.
	*/
	@Deprecated
	public int getLineIncrement() {
	return lineIncrement;
	}

	/**
	* Sets the block increment for this scroll bar.
	* <p>
	* The block increment is the value that is added or subtracted
	* when the user activates the block increment area of the
	* scroll bar, generally through a mouse or keyboard gesture
	* that the scroll bar receives as an adjustment event.
	* The block increment must be greater than zero.
	* Attepts to set the block increment to a value lower than 1
	* will result in a value of 1 being set.
	*
	* @param v the amount by which to increment or decrement
	* the scroll bar's value
	* @see java.awt.Scrollbar#getBlockIncrement
	* @since JDK1.1
	*/
	public void setBlockIncrement(int v) {
	setPageIncrement(v);
	}

	/**
	* @deprecated As of JDK version 1.1,
	* replaced by <code>setBlockIncrement()</code>.
	*/
	@Deprecated
	public synchronized void setPageIncrement(int v) {
	int tmp = (v < 1) ? 1 : v;

	if (pageIncrement == tmp) {
	return;
	}
	pageIncrement = tmp;

	ScrollbarPeer peer = (ScrollbarPeer)this.peer;
	if (peer != null) {
	peer.setPageIncrement(pageIncrement);
	}
	}

	/**
	* Gets the block increment of this scroll bar.
	* <p>
	* The block increment is the value that is added or subtracted
	* when the user activates the block increment area of the
	* scroll bar, generally through a mouse or keyboard gesture
	* that the scroll bar receives as an adjustment event.
	* The block increment must be greater than zero.
	*
	* @return the block increment of this scroll bar
	* @see java.awt.Scrollbar#setBlockIncrement
	* @since JDK1.1
	*/
	public int getBlockIncrement() {
	return getPageIncrement();
	}

	/**
	* @deprecated As of JDK version 1.1,
	* replaced by <code>getBlockIncrement()</code>.
	*/
	@Deprecated
	public int getPageIncrement() {
	return pageIncrement;
	}

	/**
	* Sets the values of four properties for this scroll bar:
	* <code>value</code>, <code>visibleAmount</code>,
	* <code>minimum</code>, and <code>maximum</code>.
	* If the values supplied for these properties are inconsistent
	* or incorrect, they will be changed to ensure consistency.
	* <p>
	* This method simultaneously and synchronously sets the values
	* of four scroll bar properties, assuring that the values of
	* these properties are mutually consistent. It enforces the
	* following constraints:
	* <code>maximum</code> must be greater than <code>minimum</code>,
	* <code>maximum - minimum</code> must not be greater
	* than <code>Integer.MAX_VALUE</code>,
	* <code>visibleAmount</code> must be greater than zero.
	* <code>visibleAmount</code> must not be greater than
	* <code>maximum - minimum</code>,
	* <code>value</code> must not be less than <code>minimum</code>,
	* and <code>value</code> must not be greater than
	* <code>maximum - visibleAmount</code>
	* <p>
	* Calling this method does not fire an
	* <code>AdjustmentEvent</code>.
	*
	* @param value is the position in the current window
	* @param visible is the visible amount of the scroll bar
	* @param minimum is the minimum value of the scroll bar
	* @param maximum is the maximum value of the scroll bar
	* @see #setMinimum
	* @see #setMaximum
	* @see #setVisibleAmount
	* @see #setValue
	*/
	public void setValues(int value, int visible, int minimum, int maximum) {
	int oldValue;
	synchronized (this) {
	if (minimum == Integer.MAX_VALUE) {
	minimum = Integer.MAX_VALUE - 1;
	}
	if (maximum <= minimum) {
	maximum = minimum + 1;
	}

	long maxMinusMin = (long) maximum - (long) minimum;
	if (maxMinusMin > Integer.MAX_VALUE) {
	maxMinusMin = Integer.MAX_VALUE;
	maximum = minimum + (int) maxMinusMin;
	}
	if (visible > (int) maxMinusMin) {
	visible = (int) maxMinusMin;
	}
	if (visible < 1) {
	visible = 1;
	}

	if (value < minimum) {
	value = minimum;
	}
	if (value > maximum - visible) {
	value = maximum - visible;
	}

	oldValue = this.value;
	this.value = value;
	this.visibleAmount = visible;
	this.minimum = minimum;
	this.maximum = maximum;
	ScrollbarPeer peer = (ScrollbarPeer)this.peer;
	if (peer != null) {
	peer.setValues(value, visibleAmount, minimum, maximum);
	}
	}

	if ((oldValue != value) && (accessibleContext != null)) {
	accessibleContext.firePropertyChange(
	AccessibleContext.ACCESSIBLE_VALUE_PROPERTY,
	Integer.valueOf(oldValue),
	Integer.valueOf(value));
	}
	}

	/**
	* Returns true if the value is in the process of changing as a
	* result of actions being taken by the user.
	*
	* @return the value of the <code>valueIsAdjusting</code> property
	* @see #setValueIsAdjusting
	* @since 1.4
	*/
	public boolean getValueIsAdjusting() {
	return isAdjusting;
	}

	/**
	* Sets the <code>valueIsAdjusting</code> property.
	*
	* @param b new adjustment-in-progress status
	* @see #getValueIsAdjusting
	* @since 1.4
	*/
	public void setValueIsAdjusting(boolean b) {
	boolean oldValue;

	synchronized (this) {
	oldValue = isAdjusting;
	isAdjusting = b;
	}

	if ((oldValue != b) && (accessibleContext != null)) {
	accessibleContext.firePropertyChange(
	AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
	((oldValue) ? AccessibleState.BUSY : null),
	((b) ? AccessibleState.BUSY : null));
	}
	}



	/**
	* Adds the specified adjustment listener to receive instances of
	* <code>AdjustmentEvent</code> from this scroll bar.
	* If l is <code>null</code>, no exception is thrown and no
	* action is performed.
	* <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
	* >AWT Threading Issues</a> for details on AWT's threading model.
	*
	* @param l the adjustment listener
	* @see #removeAdjustmentListener
	* @see #getAdjustmentListeners
	* @see java.awt.event.AdjustmentEvent
	* @see java.awt.event.AdjustmentListener
	* @since JDK1.1
	*/
	public synchronized void addAdjustmentListener(AdjustmentListener l) {
	if (l == null) {
	return;
	}
	adjustmentListener = AWTEventMulticaster.add(adjustmentListener, l);
	newEventsOnly = true;
	}

	/**
	* Removes the specified adjustment listener so that it no longer
	* receives instances of <code>AdjustmentEvent</code> from this scroll bar.
	* If l is <code>null</code>, no exception is thrown and no action
	* is performed.
	* <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
	* >AWT Threading Issues</a> for details on AWT's threading model.
	*
	* @param l the adjustment listener
	* @see #addAdjustmentListener
	* @see #getAdjustmentListeners
	* @see java.awt.event.AdjustmentEvent
	* @see java.awt.event.AdjustmentListener
	* @since JDK1.1
	*/
	public synchronized void removeAdjustmentListener(AdjustmentListener l) {
	if (l == null) {
	return;
	}
	adjustmentListener = AWTEventMulticaster.remove(adjustmentListener, l);
	}

	/**
	* Returns an array of all the adjustment listeners
	* registered on this scrollbar.
	*
	* @return all of this scrollbar's <code>AdjustmentListener</code>s
	* or an empty array if no adjustment
	* listeners are currently registered
	* @see #addAdjustmentListener
	* @see #removeAdjustmentListener
	* @see java.awt.event.AdjustmentEvent
	* @see java.awt.event.AdjustmentListener
	* @since 1.4
	*/
	public synchronized AdjustmentListener[] getAdjustmentListeners() {
	return getListeners(AdjustmentListener.class);
	}

	/**
	* Returns an array of all the objects currently registered
	* as <code><em>Foo</em>Listener</code>s
	* upon this <code>Scrollbar</code>.
	* <code><em>Foo</em>Listener</code>s are registered using the
	* <code>add<em>Foo</em>Listener</code> method.
	* <p>
	* You can specify the <code>listenerType</code> argument
	* with a class literal, such as
	* <code><em>Foo</em>Listener.class</code>.
	* For example, you can query a
	* <code>Scrollbar</code> <code>c</code>
	* for its mouse listeners with the following code:
	*
	* <pre>MouseListener[] mls = (MouseListener[])(c.getListeners(MouseListener.class));</pre>
	*
	* If no such listeners exist, this method returns an empty array.
	*
	* @param listenerType the type of listeners requested; this parameter
	* should specify an interface that descends from
	* <code>java.util.EventListener</code>
	* @return an array of all objects registered as
	* <code><em>Foo</em>Listener</code>s on this component,
	* or an empty array if no such listeners have been added
	* @exception ClassCastException if <code>listenerType</code>
	* doesn't specify a class or interface that implements
	* <code>java.util.EventListener</code>
	*
	* @since 1.3
	*/
	public <T extends EventListener> T[] getListeners(Class<T> listenerType) {
	EventListener l = null;
	if (listenerType == AdjustmentListener.class) {
	l = adjustmentListener;
	} else {
	return super.getListeners(listenerType);
	}
	return AWTEventMulticaster.getListeners(l, listenerType);
	}

	// REMIND: remove when filtering is done at lower level
	boolean eventEnabled(AWTEvent e) {
	if (e.id == AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED) {
	if ((eventMask & AWTEvent.ADJUSTMENT_EVENT_MASK) != 0 \|\|
	adjustmentListener != null) {
	return true;
	}
	return false;
	}
	return super.eventEnabled(e);
	}

	/**
	* Processes events on this scroll bar. If the event is an
	* instance of <code>AdjustmentEvent</code>, it invokes the
	* <code>processAdjustmentEvent</code> method.
	* Otherwise, it invokes its superclass's
	* <code>processEvent</code> method.
	* <p>Note that if the event parameter is <code>null</code>
	* the behavior is unspecified and may result in an
	* exception.
	*
	* @param e the event
	* @see java.awt.event.AdjustmentEvent
	* @see java.awt.Scrollbar#processAdjustmentEvent
	* @since JDK1.1
	*/
	protected void processEvent(AWTEvent e) {
	if (e instanceof AdjustmentEvent) {
	processAdjustmentEvent((AdjustmentEvent)e);
	return;
	}
	super.processEvent(e);
	}

	/**
	* Processes adjustment events occurring on this
	* scrollbar by dispatching them to any registered
	* <code>AdjustmentListener</code> objects.
	* <p>
	* This method is not called unless adjustment events are
	* enabled for this component. Adjustment events are enabled
	* when one of the following occurs:
	* <ul>
	* <li>An <code>AdjustmentListener</code> object is registered
	* via <code>addAdjustmentListener</code>.
	* <li>Adjustment events are enabled via <code>enableEvents</code>.
	* </ul>
	* <p>Note that if the event parameter is <code>null</code>
	* the behavior is unspecified and may result in an
	* exception.
	*
	* @param e the adjustment event
	* @see java.awt.event.AdjustmentEvent
	* @see java.awt.event.AdjustmentListener
	* @see java.awt.Scrollbar#addAdjustmentListener
	* @see java.awt.Component#enableEvents
	* @since JDK1.1
	*/
	protected void processAdjustmentEvent(AdjustmentEvent e) {
	AdjustmentListener listener = adjustmentListener;
	if (listener != null) {
	listener.adjustmentValueChanged(e);
	}
	}

	/**
	* Returns a string representing the state of this <code>Scrollbar</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 the parameter string of this scroll bar
	*/
	protected String paramString() {
	return super.paramString() +
	",val=" + value +
	",vis=" + visibleAmount +
	",min=" + minimum +
	",max=" + maximum +
	((orientation == VERTICAL) ? ",vert" : ",horz") +
	",isAdjusting=" + isAdjusting;
	}


	/* Serialization support.
	*/

	/**
	* The scroll bar's serialized Data Version.
	*
	* @serial
	*/
	private int scrollbarSerializedDataVersion = 1;

	/**
	* Writes default serializable fields to stream. Writes
	* a list of serializable <code>AdjustmentListeners</code>
	* as optional data. The non-serializable listeners are
	* detected and no attempt is made to serialize them.
	*
	* @param s the <code>ObjectOutputStream</code> to write
	* @serialData <code>null</code> terminated sequence of 0
	* or more pairs; the pair consists of a <code>String</code>
	* and an <code>Object</code>; the <code>String</code> indicates
	* the type of object and is one of the following:
	* <code>adjustmentListenerK</code> indicating an
	* <code>AdjustmentListener</code> object
	*
	* @see AWTEventMulticaster#save(ObjectOutputStream, String, EventListener)
	* @see java.awt.Component#adjustmentListenerK
	* @see #readObject(ObjectInputStream)
	*/
	private void writeObject(ObjectOutputStream s)
	throws IOException
	{
	s.defaultWriteObject();

	AWTEventMulticaster.save(s, adjustmentListenerK, adjustmentListener);
	s.writeObject(null);
	}

	/**
	* Reads the <code>ObjectInputStream</code> and if
	* it isn't <code>null</code> adds a listener to
	* receive adjustment events fired by the
	* <code>Scrollbar</code>.
	* Unrecognized keys or values will be ignored.
	*
	* @param s the <code>ObjectInputStream</code> to read
	* @exception HeadlessException if
	* <code>GraphicsEnvironment.isHeadless</code> returns
	* <code>true</code>
	* @see java.awt.GraphicsEnvironment#isHeadless
	* @see #writeObject(ObjectOutputStream)
	*/
	private void readObject(ObjectInputStream s)
	throws ClassNotFoundException, IOException, HeadlessException
	{
	GraphicsEnvironment.checkHeadless();
	s.defaultReadObject();

	Object keyOrNull;
	while(null != (keyOrNull = s.readObject())) {
	String key = ((String)keyOrNull).intern();

	if (adjustmentListenerK == key)
	addAdjustmentListener((AdjustmentListener)(s.readObject()));

	else // skip value for unrecognized key
	s.readObject();
	}
	}


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

	/**
	* Gets the <code>AccessibleContext</code> associated with this
	* <code>Scrollbar</code>. For scrollbars, the
	* <code>AccessibleContext</code> takes the form of an
	* <code>AccessibleAWTScrollBar</code>. A new
	* <code>AccessibleAWTScrollBar</code> instance is created if necessary.
	*
	* @return an <code>AccessibleAWTScrollBar</code> that serves as the
	* <code>AccessibleContext</code> of this <code>ScrollBar</code>
	* @since 1.3
	*/
	public AccessibleContext getAccessibleContext() {
	if (accessibleContext == null) {
	accessibleContext = new AccessibleAWTScrollBar();
	}
	return accessibleContext;
	}

	/**
	* This class implements accessibility support for the
	* <code>Scrollbar</code> class. It provides an implementation of
	* the Java Accessibility API appropriate to scrollbar
	* user-interface elements.
	* @since 1.3
	*/
	protected class AccessibleAWTScrollBar extends AccessibleAWTComponent
	implements AccessibleValue
	{
	/*
	* JDK 1.3 serialVersionUID
	*/
	private static final long serialVersionUID = -344337268523697807L;

	/**
	* Get the state set of this object.
	*
	* @return an instance of <code>AccessibleState</code>
	* containing the current state of the object
	* @see AccessibleState
	*/
	public AccessibleStateSet getAccessibleStateSet() {
	AccessibleStateSet states = super.getAccessibleStateSet();
	if (getValueIsAdjusting()) {
	states.add(AccessibleState.BUSY);
	}
	if (getOrientation() == VERTICAL) {
	states.add(AccessibleState.VERTICAL);
	} else {
	states.add(AccessibleState.HORIZONTAL);
	}
	return states;
	}

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

	/**
	* Get the <code>AccessibleValue</code> associated with this
	* object. In the implementation of the Java Accessibility
	* API for this class, return this object, which is
	* responsible for implementing the
	* <code>AccessibleValue</code> interface on behalf of itself.
	*
	* @return this object
	*/
	public AccessibleValue getAccessibleValue() {
	return this;
	}

	/**
	* Get the accessible value of this object.
	*
	* @return The current value of this object.
	*/
	public Number getCurrentAccessibleValue() {
	return Integer.valueOf(getValue());
	}

	/**
	* Set the value of this object as a Number.
	*
	* @return True if the value was set.
	*/
	public boolean setCurrentAccessibleValue(Number n) {
	if (n instanceof Integer) {
	setValue(n.intValue());
	return true;
	} else {
	return false;
	}
	}

	/**
	* Get the minimum accessible value of this object.
	*
	* @return The minimum value of this object.
	*/
	public Number getMinimumAccessibleValue() {
	return Integer.valueOf(getMinimum());
	}

	/**
	* Get the maximum accessible value of this object.
	*
	* @return The maximum value of this object.
	*/
	public Number getMaximumAccessibleValue() {
	return Integer.valueOf(getMaximum());
	}

	} // AccessibleAWTScrollBar

	}

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