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

⏎ javax/management/timer/TimerNotification.java

/*
 * Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.management.timer;

/**
 * This class provides definitions of the notifications sent by timer MBeans.
 * <BR>It defines a timer notification identifier which allows to retrieve a timer notification
 * from the list of notifications of a timer MBean.
 * <P>
 * The timer notifications are created and handled by the timer MBean.
 *
 * @since 1.5
 */
public class TimerNotification extends javax.management.Notification {


    /* Serial version */
    private static final long serialVersionUID = 1798492029603825750L;

    /*
     * ------------------------------------------
     *  PRIVATE VARIABLES
     * ------------------------------------------
     */

    /**
     * @serial Timer notification identifier.
     *         This identifier is used to retrieve a timer notification from the timer list of notifications.
     */
    private Integer notificationID;


    /*
     * ------------------------------------------
     *  CONSTRUCTORS
     * ------------------------------------------
     */

    /**
     * Creates a timer notification object.
     *
     * @param type The notification type.
     * @param source The notification producer.
     * @param sequenceNumber The notification sequence number within the source object.
     * @param timeStamp The notification emission date.
     * @param msg The notification message.
     * @param id The notification identifier.
     *
     */
    public TimerNotification(String type, Object source, long sequenceNumber, long timeStamp, String msg, Integer id) {

        super(type, source, sequenceNumber, timeStamp, msg);
        this.notificationID = id;
    }

    /*
     * ------------------------------------------
     *  PUBLIC METHODS
     * ------------------------------------------
     */

    // GETTERS AND SETTERS
    //--------------------

    /**
     * Gets the identifier of this timer notification.
     *
     * @return The identifier.
     */
    public Integer getNotificationID() {
        return notificationID;
    }

    /*
     * ------------------------------------------
     *  PACKAGE METHODS
     * ------------------------------------------
     */

    /**
     * Creates and returns a copy of this object.
     *
     */
    Object cloneTimerNotification() {

        TimerNotification clone = new TimerNotification(this.getType(), this.getSource(), this.getSequenceNumber(),
                                                        this.getTimeStamp(), this.getMessage(), notificationID);
        clone.setUserData(this.getUserData());
        return clone;
    }
}

⏎ javax/management/timer/TimerNotification.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

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

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

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