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/accessibility/AccessibleAction.java

/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package javax.accessibility;

/**
 * The AccessibleAction interface should be supported by any object
 * that can perform one or more actions.  This interface
 * provides the standard mechanism for an assistive technology to determine
 * what those actions are as well as tell the object to perform them.
 * Any object that can be manipulated should support this
 * interface.  Applications can determine if an object supports the
 * AccessibleAction interface by first obtaining its AccessibleContext (see
 * {@link Accessible}) and then calling the {@link AccessibleContext#getAccessibleAction}
 * method.  If the return value is not null, the object supports this interface.
 *
 * @see Accessible
 * @see Accessible#getAccessibleContext
 * @see AccessibleContext
 * @see AccessibleContext#getAccessibleAction
 *
 * @author      Peter Korn
 * @author      Hans Muller
 * @author      Willie Walker
 * @author      Lynn Monsanto
 */
public interface AccessibleAction {

    /**
     * An action which causes a tree node to
     * collapse if expanded and expand if collapsed.
     * @since 1.5
     */
    public static final String TOGGLE_EXPAND =
        new String ("toggleexpand");

    /**
     * An action which increments a value.
     * @since 1.5
     */
    public static final String INCREMENT =
        new String ("increment");


    /**
     * An action which decrements a value.
     * @since 1.5
     */
    public static final String DECREMENT =
        new String ("decrement");

    /**
     * An action which causes a component to execute its default action.
     * @since 1.6
     */
    public static final String CLICK = new String("click");

    /**
     * An action which causes a popup to become visible if it is hidden and
     * hidden if it is visible.
     * @since 1.6
     */
    public static final String TOGGLE_POPUP = new String("toggle popup");

    /**
     * Returns the number of accessible actions available in this object
     * If there are more than one, the first one is considered the "default"
     * action of the object.
     *
     * @return the zero-based number of Actions in this object
     */
    public int getAccessibleActionCount();

    /**
     * Returns a description of the specified action of the object.
     *
     * @param i zero-based index of the actions
     * @return a String description of the action
     * @see #getAccessibleActionCount
     */
    public String getAccessibleActionDescription(int i);

    /**
     * Performs the specified Action on the object
     *
     * @param i zero-based index of actions
     * @return true if the action was performed; otherwise false.
     * @see #getAccessibleActionCount
     */
    public boolean doAccessibleAction(int i);
}

⏎ javax/accessibility/AccessibleAction.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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