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/protocol/giopmsgheaders/MessageHandler.java

/*
 * Copyright (c) 2002, 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.impl.protocol.giopmsgheaders;

import java.io.IOException;

/**
 * Interface which allows an implementation to use
 * double dispatch when processing the various
 * concrete message types found in this package.
 */
public interface MessageHandler
{
    //
    // REVISIT - These should not throw IOException.
    //           Should be handled internally.

    /**
     * Used for message types for which we don't have concrete classes, yet,
     * such as CloseConnection and MessageError, as well as unknown types.
     */
    void handleInput(Message header) throws IOException;

    // Request
    void handleInput(RequestMessage_1_0 header) throws IOException;
    void handleInput(RequestMessage_1_1 header) throws IOException;
    void handleInput(RequestMessage_1_2 header) throws IOException;

    // Reply
    void handleInput(ReplyMessage_1_0 header) throws IOException;
    void handleInput(ReplyMessage_1_1 header) throws IOException;
    void handleInput(ReplyMessage_1_2 header) throws IOException;

    // LocateRequest
    void handleInput(LocateRequestMessage_1_0 header) throws IOException;
    void handleInput(LocateRequestMessage_1_1 header) throws IOException;
    void handleInput(LocateRequestMessage_1_2 header) throws IOException;

    // LocateReply
    void handleInput(LocateReplyMessage_1_0 header) throws IOException;
    void handleInput(LocateReplyMessage_1_1 header) throws IOException;
    void handleInput(LocateReplyMessage_1_2 header) throws IOException;

    // Fragment
    void handleInput(FragmentMessage_1_1 header) throws IOException;
    void handleInput(FragmentMessage_1_2 header) throws IOException;

    // CancelRequest
    void handleInput(CancelRequestMessage header) throws IOException;
}

⏎ com/sun/corba/se/impl/protocol/giopmsgheaders/MessageHandler.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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