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

⏎ org/w3c/dom/events/EventListener.java

/*
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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/*
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 * Copyright (c) 2000 World Wide Web Consortium,
 * (Massachusetts Institute of Technology, Institut National de
 * Recherche en Informatique et en Automatique, Keio University). All
 * Rights Reserved. This program is distributed under the W3C's Software
 * Intellectual Property License. This program is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.
 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
 */

package org.w3c.dom.events;

/**
 *  The <code>EventListener</code> interface is the primary method for
 * handling events. Users implement the <code>EventListener</code> interface
 * and register their listener on an <code>EventTarget</code> using the
 * <code>AddEventListener</code> method. The users should also remove their
 * <code>EventListener</code> from its <code>EventTarget</code> after they
 * have completed using the listener.
 * <p> When a <code>Node</code> is copied using the <code>cloneNode</code>
 * method the <code>EventListener</code>s attached to the source
 * <code>Node</code> are not attached to the copied <code>Node</code>. If
 * the user wishes the same <code>EventListener</code>s to be added to the
 * newly created copy the user must add them manually.
 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Events-20001113'>Document Object Model (DOM) Level 2 Events Specification</a>.
 * @since DOM Level 2
 */
public interface EventListener {
    /**
     *  This method is called whenever an event occurs of the type for which
     * the <code> EventListener</code> interface was registered.
     * @param evt  The <code>Event</code> contains contextual information
     *   about the event. It also contains the <code>stopPropagation</code>
     *   and <code>preventDefault</code> methods which are used in
     *   determining the event's flow and default action.
     */
    public void handleEvent(Event evt);

}

⏎ org/w3c/dom/events/EventListener.java

Or download all of them as a single archive file:

File name: jre-rt-org-1.8.0_191-src.zip
File size: 951125 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - com.* Package Source Code

⇐ JRE 8 rt.jar - javax.* Package Source Code

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