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/naming/event/NamingListener.java

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

/**
  * This interface is the root of listener interfaces that
  * handle <tt>NamingEvent</tt>s.
  * It does not make sense for a listener to implement just this interface.
  * A listener typically implements a subinterface of <tt>NamingListener</tt>,
  * such as <tt>ObjectChangeListener</tt> or <tt>NamespaceChangeListener</tt>.
  *<p>
  * This interface contains a single method, <tt>namingExceptionThrown()</tt>,
  * that must be implemented so that the listener can be notified of
  * exceptions that are thrown (by the service provider) while gathering
  * information about the events that they're interested in.
  * When this method is invoked, the listener has been automatically deregistered
  * from the <tt>EventContext</tt> with which it has registered.
  *<p>
  * For example, suppose a listener implements <tt>ObjectChangeListener</tt> and
  * registers with a <tt>EventContext</tt>.
  * Then, if the connection to the server is subsequently broken,
  * the listener will receive a <tt>NamingExceptionEvent</tt> and may
  * take some corrective action, such as notifying the user of the application.
  *
  * @author Rosanna Lee
  * @author Scott Seligman
  *
  * @see NamingEvent
  * @see NamingExceptionEvent
  * @see EventContext
  * @see EventDirContext
  * @since 1.3
  */
public interface NamingListener extends java.util.EventListener {
    /**
     * Called when a naming exception is thrown while attempting
     * to fire a <tt>NamingEvent</tt>.
     *
     * @param evt The nonnull event.
     */
    void namingExceptionThrown(NamingExceptionEvent evt);
}

⏎ javax/naming/event/NamingListener.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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