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/AccessibleKeyBinding.java

/*
 * Copyright (c) 2000, 2006, 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 AccessibleKeyBinding interface should be supported by any object
 * that has a keyboard bindings such as a keyboard mnemonic and/or keyboard
 * shortcut which can be used to select the object.  This interface provides
 * the standard mechanism for an assistive technology to determine the
 * key bindings which exist for this object.
 * Any object that has such key bindings should support this
 * interface.
 *
 * @see Accessible
 * @see Accessible#getAccessibleContext
 * @see AccessibleContext
 *
 * @author      Lynn Monsanto
 * @since 1.4
 */
public interface AccessibleKeyBinding {

    /**
     * Returns the number of key bindings for this object
     *
     * @return the zero-based number of key bindings for this object
     */
    public int getAccessibleKeyBindingCount();

    /**
     * Returns a key binding for this object.  The value returned is an
     * java.lang.Object which must be cast to appropriate type depending
     * on the underlying implementation of the key.
     *
     * @param i zero-based index of the key bindings
     * @return a javax.lang.Object which specifies the key binding
     * @see #getAccessibleKeyBindingCount
     */
    public java.lang.Object getAccessibleKeyBinding(int i);
}

⏎ javax/accessibility/AccessibleKeyBinding.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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