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/PortableServer/ServantLocatorPackage/CookieHolder.java

/*
 * Copyright (c) 1998, 2000, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package org.omg.PortableServer.ServantLocatorPackage;

/**
 * The native type PortableServer::ServantLocator::Cookie is mapped
 * to java.lang.Object. A CookieHolder class is provided for passing
 * the Cookie type as an out parameter. The CookieHolder class
 * follows exactly the same pattern as the other holder classes
 * for basic types.
 */

final public class CookieHolder implements org.omg.CORBA.portable.Streamable
{
    public java.lang.Object value;

    public CookieHolder() { }

    public CookieHolder(java.lang.Object initial) {
        value = initial;
    }

    public void _read( org.omg.CORBA.portable.InputStream is) {
        throw new org.omg.CORBA.NO_IMPLEMENT();
    }

    public void _write( org.omg.CORBA.portable.OutputStream os) {
        throw new org.omg.CORBA.NO_IMPLEMENT();
    }

    public org.omg.CORBA.TypeCode _type() {
        throw new org.omg.CORBA.NO_IMPLEMENT();
    }
}

⏎ org/omg/PortableServer/ServantLocatorPackage/CookieHolder.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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