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

⏎ com/sun/corba/se/impl/util/ORBProperties.java

/*
 * Copyright (c) 1998, 2003, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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/*
 * Licensed Materials - Property of IBM
 * RMI-IIOP v1.0
 * Copyright IBM Corp. 1998 1999  All Rights Reserved
 *
 */

package com.sun.corba.se.impl.util;

import java.io.File;
import java.io.FileOutputStream;
import java.io.PrintWriter;

public class ORBProperties {

    public static final String ORB_CLASS =
        "org.omg.CORBA.ORBClass=com.sun.corba.se.impl.orb.ORBImpl";
    public static final String ORB_SINGLETON_CLASS =
        "org.omg.CORBA.ORBSingletonClass=com.sun.corba.se.impl.orb.ORBSingleton";

    public static void main (String[] args) {

        try {
            // Check if orb.properties exists
            String javaHome = System.getProperty("java.home");
            File propFile = new File(javaHome + File.separator
                                     + "lib" + File.separator
                                     + "orb.properties");

            if (propFile.exists())
                return;

            // Write properties to orb.properties
            FileOutputStream out = new FileOutputStream(propFile);
            PrintWriter pw = new PrintWriter(out);

            try {
                pw.println(ORB_CLASS);
                pw.println(ORB_SINGLETON_CLASS);
            } finally {
                pw.close();
                out.close();
            }

        } catch (Exception ex) { }

    }
}

⏎ com/sun/corba/se/impl/util/ORBProperties.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
Download 

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