JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the com.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ com/sun/java/swing/plaf/motif/MotifSliderUI.java

/*
 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
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 *
 *
 *
 *
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 *
 *
 *
 *
 *
 *
 *
 */

package com.sun.java.swing.plaf.motif;

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Rectangle;

import javax.swing.JComponent;
import javax.swing.JSlider;
import javax.swing.plaf.ComponentUI;
import javax.swing.plaf.basic.BasicSliderUI;

import static sun.swing.SwingUtilities2.drawHLine;
import static sun.swing.SwingUtilities2.drawVLine;

/**
 * Motif Slider
 * <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.  A future release of Swing will provide support for
 * long term persistence.
 *
 * @author Jeff Dinkins
 */
public class MotifSliderUI extends BasicSliderUI {

    static final Dimension PREFERRED_HORIZONTAL_SIZE = new Dimension(164, 15);
    static final Dimension PREFERRED_VERTICAL_SIZE = new Dimension(15, 164);

    static final Dimension MINIMUM_HORIZONTAL_SIZE = new Dimension(43, 15);
    static final Dimension MINIMUM_VERTICAL_SIZE = new Dimension(15, 43);

    /**
     * MotifSliderUI Constructor
     */
    public MotifSliderUI(JSlider b)   {
        super(b);
    }

    /**
     * create a MotifSliderUI object
     */
    public static ComponentUI createUI(JComponent b)    {
        return new MotifSliderUI((JSlider)b);
    }

    public Dimension getPreferredHorizontalSize() {
        return PREFERRED_HORIZONTAL_SIZE;
    }

    public Dimension getPreferredVerticalSize() {
        return PREFERRED_VERTICAL_SIZE;
    }

    public Dimension getMinimumHorizontalSize() {
        return MINIMUM_HORIZONTAL_SIZE;
    }

    public Dimension getMinimumVerticalSize() {
        return MINIMUM_VERTICAL_SIZE;
    }

    protected Dimension getThumbSize() {
        if ( slider.getOrientation() == JSlider.HORIZONTAL ) {
            return new Dimension( 30, 15 );
        }
        else {
            return new Dimension( 15, 30 );
        }
    }

    public void paintFocus(Graphics g)  {
    }

    public void paintTrack(Graphics g)  {
    }

    public void paintThumb(Graphics g)  {
        Rectangle knobBounds = thumbRect;

        int x = knobBounds.x;
        int y = knobBounds.y;
        int w = knobBounds.width;
        int h = knobBounds.height;

        if ( slider.isEnabled() ) {
            g.setColor(slider.getForeground());
        }
        else {
            // PENDING(jeff) - the thumb should be dithered when disabled
            g.setColor(slider.getForeground().darker());
        }

        if ( slider.getOrientation() == JSlider.HORIZONTAL ) {
            g.translate(x, knobBounds.y-1);

            // fill
            g.fillRect(0, 1, w, h - 1);

            // highlight
            g.setColor(getHighlightColor());
            drawHLine(g, 0, w - 1, 1);      // top
            drawVLine(g, 0, 1, h);          // left
            drawVLine(g, w / 2, 2, h - 1);  // center

            // shadow
            g.setColor(getShadowColor());
            drawHLine(g, 0, w - 1, h);      // bottom
            drawVLine(g, w - 1, 1, h);      // right
            drawVLine(g, w / 2 - 1, 2, h);  // center

            g.translate(-x, -(knobBounds.y-1));
        }
        else {
            g.translate(knobBounds.x-1, 0);

            // fill
            g.fillRect(1, y, w - 1, h);

            // highlight
            g.setColor(getHighlightColor());
            drawHLine(g, 1, w, y);             // top
            drawVLine(g, 1, y + 1, y + h - 1); // left
            drawHLine(g, 2, w - 1, y + h / 2); // center

            // shadow
            g.setColor(getShadowColor());
            drawHLine(g, 2, w, y + h - 1);        // bottom
            drawVLine(g, w, y + h - 1, y);        // right
            drawHLine(g, 2, w - 1, y + h / 2 - 1);// center

            g.translate(-(knobBounds.x-1), 0);
        }
    }
}

⏎ com/sun/java/swing/plaf/motif/MotifSliderUI.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
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