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/ActiveEvent.java

/*
 * Copyright (c) 1997, 2002, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package java.awt;

/**
 * An interface for events that know how to dispatch themselves.
 * By implementing this interface an event can be placed upon the event
 * queue and its <code>dispatch()</code> method will be called when the event
 * is dispatched, using the <code>EventDispatchThread</code>.
 * <p>
 * This is a very useful mechanism for avoiding deadlocks. If
 * a thread is executing in a critical section (i.e., it has entered
 * one or more monitors), calling other synchronized code may
 * cause deadlocks. To avoid the potential deadlocks, an
 * <code>ActiveEvent</code> can be created to run the second section of
 * code at later time. If there is contention on the monitor,
 * the second thread will simply block until the first thread
 * has finished its work and exited its monitors.
 * <p>
 * For security reasons, it is often desirable to use an <code>ActiveEvent</code>
 * to avoid calling untrusted code from a critical thread. For
 * instance, peer implementations can use this facility to avoid
 * making calls into user code from a system thread. Doing so avoids
 * potential deadlocks and denial-of-service attacks.
 *
 * @author  Timothy Prinzing
 * @since   1.2
 */
public interface ActiveEvent {

    /**
     * Dispatch the event to its target, listeners of the events source,
     * or do whatever it is this event is supposed to do.
     */
    public void dispatch();
}

⏎ java/awt/ActiveEvent.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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