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/spi/servicecontext/ORBVersionServiceContext.java

/*
 * Copyright (c) 2000, 2003, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package com.sun.corba.se.spi.servicecontext;

import org.omg.CORBA.SystemException;
import org.omg.CORBA_2_3.portable.InputStream ;
import org.omg.CORBA_2_3.portable.OutputStream ;

import com.sun.corba.se.spi.orb.ORBVersion ;
import com.sun.corba.se.spi.orb.ORBVersionFactory ;

import com.sun.corba.se.spi.ior.iiop.GIOPVersion;
import com.sun.corba.se.spi.servicecontext.ServiceContext ;
import com.sun.corba.se.impl.orbutil.ORBConstants ;

public class ORBVersionServiceContext extends ServiceContext {

    public ORBVersionServiceContext( )
    {
        version = ORBVersionFactory.getORBVersion() ;
    }

    public ORBVersionServiceContext( ORBVersion ver )
    {
        this.version = ver ;
    }

    public ORBVersionServiceContext(InputStream is, GIOPVersion gv)
    {
        super(is, gv) ;
        // pay particular attention to where the version is being read from!
        // is contains an encapsulation, ServiceContext reads off the
        // encapsulation and leaves the pointer in the variable "in",
        // which points to the long value.

        version = ORBVersionFactory.create( in ) ;
    }

    // Required SERVICE_CONTEXT_ID and getId definitions
    public static final int SERVICE_CONTEXT_ID = ORBConstants.TAG_ORB_VERSION ;
    public int getId() { return SERVICE_CONTEXT_ID ; }

    public void writeData( OutputStream os ) throws SystemException
    {
        version.write( os ) ;
    }

    public ORBVersion getVersion()
    {
        return version ;
    }

    // current ORB Version
    private ORBVersion version = ORBVersionFactory.getORBVersion() ;

    public String toString()
    {
        return "ORBVersionServiceContext[ version=" + version + " ]" ;
    }
}

⏎ com/sun/corba/se/spi/servicecontext/ORBVersionServiceContext.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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