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/ServantObject.java

/*
 * Copyright (c) 1998, 2010, 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;

/**
 This class is part of the local stub API, the purpose of which is to provide
 high performance calls for collocated clients and servers
 (i.e. clients and servers residing in the same Java VM).
 The local stub API is supported via three additional methods on
 <code>ObjectImpl</code> and <code>Delegate</code>.
 ORB vendors may subclass this class to return additional
 request state that may be required by their implementations.
 @see ObjectImpl
 @see Delegate
*/

public class ServantObject
{
    /** The real servant. The local stub may cast this field to the expected type, and then
     * invoke the operation directly. Note, the object may or may not be the actual servant
     * instance.
     */
    public java.lang.Object servant;
}

⏎ org/omg/CORBA/portable/ServantObject.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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