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/jmx/remote/internal/NotificationBuffer.java

/*
 * Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package com.sun.jmx.remote.internal;

import java.util.Set;
import javax.management.remote.NotificationResult;
import javax.management.remote.TargetedNotification;

/** A buffer of notifications received from an MBean server. */
public interface NotificationBuffer {
    /**
     * <p>Fetch notifications that match the given listeners.</p>
     *
     * <p>The operation only considers notifications with a sequence
     * number at least <code>startSequenceNumber</code>.  It will take
     * no longer than <code>timeout</code>, and will return no more
     * than <code>maxNotifications</code> different notifications.</p>
     *
     * <p>If there are no notifications matching the criteria, the
     * operation will block until one arrives, subject to the
     * timeout.</p>
     *
     * @param filter an object that will add notifications to a
     * {@code List<TargetedNotification>} if they match the current
     * listeners with their filters.
     * @param startSequenceNumber the first sequence number to
     * consider.
     * @param timeout the maximum time to wait.  May be 0 to indicate
     * not to wait if there are no notifications.
     * @param maxNotifications the maximum number of notifications to
     * return.  May be 0 to indicate a wait for eligible notifications
     * that will return a usable <code>nextSequenceNumber</code>.  The
     * {@link TargetedNotification} array in the returned {@link
     * NotificationResult} may contain more than this number of
     * elements but will not contain more than this number of
     * different notifications.
     */
    public NotificationResult
        fetchNotifications(NotificationBufferFilter filter,
                           long startSequenceNumber,
                           long timeout,
                           int maxNotifications)
            throws InterruptedException;

    /**
     * <p>Discard this buffer.</p>
     */
    public void dispose();
}

⏎ com/sun/jmx/remote/internal/NotificationBuffer.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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