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/ServiceDetail.java

/*
 * Copyright (c) 1998, 2001, 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;

/**
 * An object that represents an ORB service: its <code>service_detail_type</code>
 * field contains the type of the ORB service, and its <code>service_detail</code>
 * field contains a description of the ORB service.

 *
 * @author RIP Team
 */
public final class ServiceDetail implements org.omg.CORBA.portable.IDLEntity
{
    /**
     * The type of the ORB service that this <code>ServiceDetail</code>
     * object represents.
     */
    public int service_detail_type;

    /**
     * The data describing the ORB service that this <code>ServiceDetail</code>
     * object represents.
     */
    public byte[] service_detail;

    /**
     * Constructs a <code>ServiceDetail</code> object with 0 for the type of
     * ORB service and an empty description.
     */
    public ServiceDetail() { }

    /**
     * Constructs a <code>ServiceDetail</code> object with the given
     * ORB service type and the given description.
     *
     * @param service_detail_type an <code>int</code> specifying the type of
     *                            ORB service
     * @param service_detail a <code>byte</code> array describing the ORB service
     */
    public ServiceDetail(int service_detail_type, byte[] service_detail) {
        this.service_detail_type = service_detail_type;
        this.service_detail = service_detail;
    }
}

⏎ org/omg/CORBA/ServiceDetail.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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