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/WindowsDesktopManager.java

/*
 * Copyright (c) 1998, 2008, 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.windows;

import javax.swing.DefaultDesktopManager;
import javax.swing.JInternalFrame;
import javax.swing.JLayeredPane;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.beans.PropertyVetoException;
import java.util.Vector;
import java.lang.ref.WeakReference;

/**
 * This class implements a DesktopManager which more closely follows
 * the MDI model than the DefaultDesktopManager.  Unlike the
 * DefaultDesktopManager policy, MDI requires that the selected
 * and activated child frames are the same, and that that frame
 * always be the top-most window.
 * <p>
 * The maximized state is managed by the DesktopManager with MDI,
 * instead of just being a property of the individual child frame.
 * This means that if the currently selected window is maximized
 * and another window is selected, that new window will be maximized.
 *
 * @see javax.swing.DefaultDesktopManager
 * @author Thomas Ball
 */
public class WindowsDesktopManager extends DefaultDesktopManager
        implements java.io.Serializable, javax.swing.plaf.UIResource {

    /* The frame which is currently selected/activated.
     * We store this value to enforce MDI's single-selection model.
     */
    private WeakReference<JInternalFrame> currentFrameRef;

    public void activateFrame(JInternalFrame f) {
        JInternalFrame currentFrame = currentFrameRef != null ?
            currentFrameRef.get() : null;
        try {
            super.activateFrame(f);
            if (currentFrame != null && f != currentFrame) {
                // If the current frame is maximized, transfer that
                // attribute to the frame being activated.
                if (currentFrame.isMaximum() &&
                    (f.getClientProperty("JInternalFrame.frameType") !=
                    "optionDialog") ) {
                    //Special case.  If key binding was used to select next
                    //frame instead of minimizing the icon via the minimize
                    //icon.
                    if (!currentFrame.isIcon()) {
                        currentFrame.setMaximum(false);
                        if (f.isMaximizable()) {
                            if (!f.isMaximum()) {
                                f.setMaximum(true);
                            } else if (f.isMaximum() && f.isIcon()) {
                                f.setIcon(false);
                            } else {
                                f.setMaximum(false);
                            }
                        }
                    }
                }
                if (currentFrame.isSelected()) {
                    currentFrame.setSelected(false);
                }
            }

            if (!f.isSelected()) {
                f.setSelected(true);
            }
        } catch (PropertyVetoException e) {}
        if (f != currentFrame) {
            currentFrameRef = new WeakReference<JInternalFrame>(f);
        }
    }

}

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