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 java.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ java/awt/peer/MouseInfoPeer.java

/*
 * Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.awt.peer;

import java.awt.Window;
import java.awt.Point;

/**
 * Peer interface for {@link MouseInfo}. This is used to get some additional
 * information about the mouse.
 *
 * The peer interfaces are intended only for use in porting
 * the AWT. They are not intended for use by application
 * developers, and developers should not implement peers
 * nor invoke any of the peer methods directly on the peer
 * instances.
 */
public interface MouseInfoPeer {

    /**
     * This method does two things: it fills the point fields with
     * the current coordinates of the mouse cursor and returns the
     * number of the screen device where the pointer is located.
     * The number of the screen device is only returned for independent
     * devices (which are not parts of a virtual screen device).
     * For virtual screen devices, 0 is returned.
     * Mouse coordinates are also calculated depending on whether
     * or not the screen device is virtual. For virtual screen
     * devices, pointer coordinates are calculated in the virtual
     * coordinate system. Otherwise, coordinates are calculated in
     * the coordinate system of the screen device where the pointer
     * is located.
     * See java.awt.GraphicsConfiguration documentation for more
     * details about virtual screen devices.
     */
    int fillPointWithCoords(Point point);

    /**
     * Returns whether or not the window is located under the mouse
     * pointer. The window is considered to be under the mouse pointer
     * if it is showing on the screen, and the mouse pointer is above
     * the part of the window that is not obscured by any other windows.
     */
    boolean isWindowUnderMouse(Window w);

}

⏎ java/awt/peer/MouseInfoPeer.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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