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/corba/ContextListImpl.java

/*
 * Copyright (c) 1996, 2002, 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.corba;

import java.util.Vector;
import org.omg.CORBA.ContextList;
import org.omg.CORBA.Bounds;
import org.omg.CORBA.ORB;

public class ContextListImpl extends ContextList
{
    private final int    INITIAL_CAPACITY       = 2;
    private final int    CAPACITY_INCREMENT     = 2;

    private org.omg.CORBA.ORB _orb;
    private Vector _contexts;

    public ContextListImpl(org.omg.CORBA.ORB orb)
    {
        // Note: This orb could be an instanceof ORBSingleton or ORB
        _orb = orb;
        _contexts = new Vector(INITIAL_CAPACITY, CAPACITY_INCREMENT);
    }

    public int count()
    {
        return _contexts.size();
    }

    public void add(String ctxt)
    {
        _contexts.addElement(ctxt);
    }

    public String item(int index)
        throws Bounds
    {
        try {
            return (String) _contexts.elementAt(index);
        } catch (ArrayIndexOutOfBoundsException e) {
            throw new Bounds();
        }
    }

    public void remove(int index)
        throws Bounds
    {
        try {
            _contexts.removeElementAt(index);
        } catch (ArrayIndexOutOfBoundsException e) {
            throw new Bounds();
        }
    }

}

⏎ com/sun/corba/se/impl/corba/ContextListImpl.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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