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/ComboBoxEditor.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;

import java.awt.*;
import java.awt.event.*;

/**
 * The editor component used for JComboBox components.
 *
 * @author Arnaud Weber
 */
public interface ComboBoxEditor {

  /** Return the component that should be added to the tree hierarchy for
    * this editor
    */
  public Component getEditorComponent();

  /** Set the item that should be edited. Cancel any editing if necessary **/
  public void setItem(Object anObject);

  /** Return the edited item **/
  public Object getItem();

  /** Ask the editor to start editing and to select everything **/
  public void selectAll();

  /** Add an ActionListener. An action event is generated when the edited item changes **/
  public void addActionListener(ActionListener l);

  /** Remove an ActionListener **/
  public void removeActionListener(ActionListener l);
}

⏎ javax/swing/ComboBoxEditor.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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