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/windows/WindowsRadioButtonUI.java

/*
 * Copyright (c) 1997, 2012, 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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 *
 *
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 *
 *
 *
 */

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

import sun.awt.AppContext;

import javax.swing.plaf.basic.*;
import javax.swing.*;
import javax.swing.plaf.*;

import java.awt.*;


/**
 * Windows rendition of the component.
 * <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.
 */
public class WindowsRadioButtonUI extends BasicRadioButtonUI
{
    private static final Object WINDOWS_RADIO_BUTTON_UI_KEY = new Object();

    protected int dashedRectGapX;
    protected int dashedRectGapY;
    protected int dashedRectGapWidth;
    protected int dashedRectGapHeight;

    protected Color focusColor;

    private boolean initialized = false;

    // ********************************
    //          Create PLAF
    // ********************************
    public static ComponentUI createUI(JComponent c) {
        AppContext appContext = AppContext.getAppContext();
        WindowsRadioButtonUI windowsRadioButtonUI =
                (WindowsRadioButtonUI) appContext.get(WINDOWS_RADIO_BUTTON_UI_KEY);
        if (windowsRadioButtonUI == null) {
            windowsRadioButtonUI = new WindowsRadioButtonUI();
            appContext.put(WINDOWS_RADIO_BUTTON_UI_KEY, windowsRadioButtonUI);
        }
        return windowsRadioButtonUI;
    }

    // ********************************
    //           Defaults
    // ********************************
    public void installDefaults(AbstractButton b) {
        super.installDefaults(b);
        if(!initialized) {
            dashedRectGapX = ((Integer)UIManager.get("Button.dashedRectGapX")).intValue();
            dashedRectGapY = ((Integer)UIManager.get("Button.dashedRectGapY")).intValue();
            dashedRectGapWidth = ((Integer)UIManager.get("Button.dashedRectGapWidth")).intValue();
            dashedRectGapHeight = ((Integer)UIManager.get("Button.dashedRectGapHeight")).intValue();
            focusColor = UIManager.getColor(getPropertyPrefix() + "focus");
            initialized = true;
        }
        if (XPStyle.getXP() != null) {
            LookAndFeel.installProperty(b, "rolloverEnabled", Boolean.TRUE);
        }
    }

    protected void uninstallDefaults(AbstractButton b) {
        super.uninstallDefaults(b);
        initialized = false;
    }

    protected Color getFocusColor() {
        return focusColor;
    }

    // ********************************
    //          Paint Methods
    // ********************************

    /**
     * Overridden method to render the text without the mnemonic
     */
    protected void paintText(Graphics g, AbstractButton b, Rectangle textRect, String text) {
        WindowsGraphicsUtils.paintText(g, b, textRect, text, getTextShiftOffset());
    }


    protected void paintFocus(Graphics g, Rectangle textRect, Dimension d){
        g.setColor(getFocusColor());
        BasicGraphicsUtils.drawDashedRect(g, textRect.x, textRect.y, textRect.width, textRect.height);
    }

    // ********************************
    //          Layout Methods
    // ********************************
    public Dimension getPreferredSize(JComponent c) {
        Dimension d = super.getPreferredSize(c);

        /* Ensure that the width and height of the button is odd,
         * to allow for the focus line if focus is painted
         */
        AbstractButton b = (AbstractButton)c;
        if (d != null && b.isFocusPainted()) {
            if(d.width % 2 == 0) { d.width += 1; }
            if(d.height % 2 == 0) { d.height += 1; }
        }
        return d;
    }

}

⏎ com/sun/java/swing/plaf/windows/WindowsRadioButtonUI.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
Download 

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