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/swing/event/DocumentListener.java

/*
 * Copyright (c) 1997, 1998, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package javax.swing.event;

import java.util.EventListener;

/**
 * Interface for an observer to register to receive notifications
 * of changes to a text document.
 * <p>
 * The default implementation of
 * the Document interface (AbstractDocument) supports asynchronous
 * mutations.  If this feature is used (i.e. mutations are made
 * from a thread other than the Swing event thread), the listeners
 * will be notified via the mutating thread.  <em>This means that
 * if asynchronous updates are made, the implementation of this
 * interface must be threadsafe</em>!
 * <p>
 * The DocumentEvent notification is based upon the JavaBeans
 * event model.  There is no guarantee about the order of delivery
 * to listeners, and all listeners must be notified prior to making
 * further mutations to the Document.  <em>This means implementations
 * of the DocumentListener may not mutate the source of the event
 * (i.e. the associated Document)</em>.
 *
 * @author  Timothy Prinzing
 * @see javax.swing.text.Document
 * @see javax.swing.text.StyledDocument
 * @see DocumentEvent
 */
public interface DocumentListener extends EventListener {

    /**
     * Gives notification that there was an insert into the document.  The
     * range given by the DocumentEvent bounds the freshly inserted region.
     *
     * @param e the document event
     */
    public void insertUpdate(DocumentEvent e);

    /**
     * Gives notification that a portion of the document has been
     * removed.  The range is given in terms of what the view last
     * saw (that is, before updating sticky positions).
     *
     * @param e the document event
     */
    public void removeUpdate(DocumentEvent e);

    /**
     * Gives notification that an attribute or set of attributes changed.
     *
     * @param e the document event
     */
    public void changedUpdate(DocumentEvent e);
}

⏎ javax/swing/event/DocumentListener.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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