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/orb/ORBVersion.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.orb ;

import org.omg.CORBA.portable.OutputStream ;

public interface ORBVersion extends Comparable
{
    byte FOREIGN = 0 ;          // ORB from another vendor
    byte OLD = 1 ;              // JDK 1.3.0 or earlier
    byte NEW = 2 ;              // JDK 1.3.1 FCS
    byte JDK1_3_1_01 = 3;       // JDK1_3_1_01 patch
    byte NEWER = 10 ;           // JDK 1.4.x
    byte PEORB = 20 ;           // PEORB in JDK 1.5, S1AS 8, J2EE 1.4

    byte getORBType() ;

    void write( OutputStream os ) ;

    public boolean lessThan( ORBVersion version ) ;
}

⏎ com/sun/corba/se/spi/orb/ORBVersion.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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