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/portable/Delegate.java

/*
 * Copyright (c) 1999, 2003, 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.portable;

import org.omg.PortableServer.Servant;
import org.omg.PortableServer.POA;

/**
 * The portability package contains interfaces and classes
 * that are designed for and intended to be used by ORB
 * implementor. It exposes the publicly defined APIs that
 * are used to connect stubs and skeletons to the ORB.
 * The Delegate interface provides the ORB vendor specific
 * implementation of PortableServer::Servant.
 * Conformant to spec CORBA V2.3.1, ptc/00-01-08.pdf
 */
public interface Delegate {
/**
 * Convenience method that returns the instance of the ORB
 * currently associated with the Servant.
 * @param Self the servant.
 * @return ORB associated with the Servant.
 */
    org.omg.CORBA.ORB orb(Servant Self);

/**
 * This allows the servant to obtain the object reference for
 * the target CORBA Object it is incarnating for that request.
 * @param Self the servant.
 * @return Object reference associated with the request.
 */
    org.omg.CORBA.Object this_object(Servant Self);

/**
 * The method _poa() is equivalent to
 * calling PortableServer::Current:get_POA.
 * @param Self the servant.
 * @return POA associated with the servant.
 */
    POA poa(Servant Self);

/**
 * The method _object_id() is equivalent
 * to calling PortableServer::Current::get_object_id.
 * @param Self the servant.
 * @return ObjectId associated with this servant.
 */
    byte[] object_id(Servant Self);

/**
 * The default behavior of this function is to return the
 * root POA from the ORB instance associated with the servant.
 * @param Self the servant.
 * @return POA associated with the servant class.
 */
    POA default_POA(Servant Self);

/**
 * This method checks to see if the specified repid is present
 * on the list returned by _all_interfaces() or is the
 * repository id for the generic CORBA Object.
 * @param Self the servant.
 * @param Repository_Id the repository_id to be checked in the
 *            repository list or against the id of generic CORBA
 *            object.
 * @return boolean indicating whether the specified repid is
 *         in the list or is same as that got generic CORBA
 *         object.
 */
    boolean is_a(Servant Self, String Repository_Id);

/**
 * This operation is used to check for the existence of the
 * Object.
 * @param Self the servant.
 * @return boolean true to indicate that object does not exist,
 *                 and false otherwise.
 */
    boolean non_existent(Servant Self);
    //Simon And Ken Will Ask About Editorial Changes
    //In Idl To Java For The Following Signature.

/**
 * This operation returns an object in the Interface Repository
 * which provides type information that may be useful to a program.
 * @param self the servant.
 * @return type information corresponding to the object.
 */
    // The get_interface() method has been replaced by get_interface_def()
    //org.omg.CORBA.Object get_interface(Servant Self);

    org.omg.CORBA.Object get_interface_def(Servant self);
}

⏎ org/omg/PortableServer/portable/Delegate.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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