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/AccessibleStreamable.java

/*
 * Copyright (c) 2003, 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;

import java.io.InputStream;
import java.awt.datatransfer.DataFlavor;

/**
 *
 * The <code>AccessibleStreamable</code> interface should be implemented
 * by the <code>AccessibleContext</code> of any component that presents the
 * raw stream behind a component on the display screen.  Examples of such
 * components are HTML, bitmap images and MathML.  An object that implements
 * <code>AccessibleStreamable</code> provides two things: a list of MIME
 * types supported by the object and a streaming interface for each MIME type to
 * get the data.
 *
 * @author Lynn Monsanto
 * @author Peter Korn
 *
 * @see javax.accessibility.AccessibleContext
 * @since 1.5
 */
public interface AccessibleStreamable {
    /**
      * Returns an array of DataFlavor objects for the MIME types
      * this object supports.
      *
      * @return an array of DataFlavor objects for the MIME types
      * this object supports.
      */
     DataFlavor[] getMimeTypes();

    /**
      * Returns an InputStream for a DataFlavor
      *
      * @param flavor the DataFlavor
      * @return an ImputStream if an ImputStream for this DataFlavor exists.
      * Otherwise, null is returned.
      */
     InputStream getStream(DataFlavor flavor);
}

⏎ javax/accessibility/AccessibleStreamable.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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