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/WindowsDesktopIconUI.java

/*
 * Copyright (c) 1997, 2004, 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 java.awt.*;
import javax.swing.plaf.*;
import javax.swing.plaf.basic.*;
import javax.swing.*;
import javax.swing.border.*;



/**
 * Windows icon for a minimized window on the desktop.
 * <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 WindowsDesktopIconUI extends BasicDesktopIconUI {
    private int width;

    public static ComponentUI createUI(JComponent c) {
        return new WindowsDesktopIconUI();
    }

    public void installDefaults() {
        super.installDefaults();
        width = UIManager.getInt("DesktopIcon.width");
    }

    public void installUI(JComponent c)   {
        super.installUI(c);

        c.setOpaque(XPStyle.getXP() == null);
    }

    // Uninstall the listeners added by the WindowsInternalFrameTitlePane
    public void uninstallUI(JComponent c) {
        WindowsInternalFrameTitlePane thePane =
                                        (WindowsInternalFrameTitlePane)iconPane;
        super.uninstallUI(c);
        thePane.uninstallListeners();
    }

    protected void installComponents() {
        iconPane = new WindowsInternalFrameTitlePane(frame);
        desktopIcon.setLayout(new BorderLayout());
        desktopIcon.add(iconPane, BorderLayout.CENTER);

        if (XPStyle.getXP() != null) {
            desktopIcon.setBorder(null);
        }
    }

    public Dimension getPreferredSize(JComponent c) {
        // Windows desktop icons can not be resized.  Therefore, we should
        // always return the minimum size of the desktop icon. See
        // getMinimumSize(JComponent c).
        return getMinimumSize(c);
    }

    /**
     * Windows desktop icons are restricted to a width of 160 pixels by
     * default.  This value is retrieved by the DesktopIcon.width property.
     */
    public Dimension getMinimumSize(JComponent c) {
        Dimension dim = super.getMinimumSize(c);
        dim.width = width;
        return dim;
    }
}

⏎ com/sun/java/swing/plaf/windows/WindowsDesktopIconUI.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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