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 org.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ org/omg/CORBA/portable/Streamable.java

/*
 * Copyright (c) 1997, 1999, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package org.omg.CORBA.portable;

import org.omg.CORBA.TypeCode;

/**
 * The base class for the Holder classess of all complex
 * IDL types. The ORB treats all generated Holders as Streamable to invoke
 * the methods for marshalling and unmarshalling.
 *
 * @since   JDK1.2
 */

public interface Streamable {
    /**
     * Reads data from <code>istream</code> and initalizes the
     * <code>value</code> field of the Holder with the unmarshalled data.
     *
     * @param     istream   the InputStream that represents the CDR data from the wire.
     */
    void _read(InputStream istream);
    /**
     * Marshals to <code>ostream</code> the value in the
     * <code>value</code> field of the Holder.
     *
     * @param     ostream   the CDR OutputStream
     */
    void _write(OutputStream ostream);

    /**
     * Retrieves the <code>TypeCode</code> object corresponding to the value
     * in the <code>value</code> field of the Holder.
     *
     * @return    the <code>TypeCode</code> object for the value held in the holder
     */
    TypeCode _type();
}

⏎ org/omg/CORBA/portable/Streamable.java

Or download all of them as a single archive file:

File name: jre-rt-org-1.8.0_191-src.zip
File size: 951125 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - com.* Package Source Code

⇐ JRE 8 rt.jar - javax.* Package Source Code

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