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/RobotPeer.java

/*
 * Copyright (c) 1999, 2008, 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.*;

/**
 * RobotPeer defines an interface whereby toolkits support automated testing
 * by allowing native input events to be generated from Java code.
 *
 * This interface should not be directly imported by code outside the
 * java.awt.* hierarchy; it is not to be considered public and is subject
 * to change.
 *
 * @author      Robi Khan
 */
public interface RobotPeer
{
    /**
     * Moves the mouse pointer to the specified screen location.
     *
     * @param x the X location on screen
     * @param y the Y location on screen
     *
     * @see Robot#mouseMove(int, int)
     */
    void mouseMove(int x, int y);

    /**
     * Simulates a mouse press with the specified button(s).
     *
     * @param buttons the button mask
     *
     * @see Robot#mousePress(int)
     */
    void mousePress(int buttons);

    /**
     * Simulates a mouse release with the specified button(s).
     *
     * @param buttons the button mask
     *
     * @see Robot#mouseRelease(int)
     */
    void mouseRelease(int buttons);

    /**
     * Simulates mouse wheel action.
     *
     * @param wheelAmt number of notches to move the mouse wheel
     *
     * @see Robot#mouseWheel(int)
     */
    void mouseWheel(int wheelAmt);

    /**
     * Simulates a key press of the specified key.
     *
     * @param keycode the key code to press
     *
     * @see Robot#keyPress(int)
     */
    void keyPress(int keycode);

    /**
     * Simulates a key release of the specified key.
     *
     * @param keycode the key code to release
     *
     * @see Robot#keyRelease(int)
     */
    void keyRelease(int keycode);

    /**
     * Gets the RGB value of the specified pixel on screen.
     *
     * @param x the X screen coordinate
     * @param y the Y screen coordinate
     *
     * @return the RGB value of the specified pixel on screen
     *
     * @see Robot#getPixelColor(int, int)
     */
    int getRGBPixel(int x, int y);

    /**
     * Gets the RGB values of the specified screen area as an array.
     *
     * @param bounds the screen area to capture the RGB values from
     *
     * @return the RGB values of the specified screen area
     *
     * @see Robot#createScreenCapture(Rectangle)
     */
    int[] getRGBPixels(Rectangle bounds);

    /**
     * Disposes the robot peer when it is not needed anymore.
     */
    void dispose();
}

⏎ java/awt/peer/RobotPeer.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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