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/encoding/BufferManagerRead.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.impl.encoding;

import java.nio.ByteBuffer;
import com.sun.corba.se.impl.encoding.ByteBufferWithInfo;
import com.sun.corba.se.impl.protocol.giopmsgheaders.FragmentMessage;
import com.sun.corba.se.impl.protocol.giopmsgheaders.Message;

public interface BufferManagerRead
{
    /**
     * Case: Called from ReaderThread on complete message or fragments.
     *       The given buf may be entire message or a fragment.
     *
     *  The ReaderThread finds the ReadBufferManager instance either in
     *  in a fragment map (when collecting - GIOP 1.2 phase 1) or
     *  in an active server requests map (when streaming - GIOP 1.2 phase 2).
     *
     *  As a model for implementation see IIOPInputStream's
     *  constructor of the same name. There are going to be some variations.
     *
     */

    public void processFragment ( ByteBuffer byteBuffer,
        FragmentMessage header);


    /**
     * Case: called from CDRInputStream constructor before unmarshaling.
     *
     * Does:
     *
     *  this.bufQ.get()
     *
     *  If streaming then sync on bufQ and wait if empty.
     */


    /**
     * Case: called from CDRInputStream.grow.
     *
     * Does:
     *
     *  this.bufQ.get()
     *
     *  If streaming then sync on bufQ and wait if empty.
     */

    public ByteBufferWithInfo underflow (ByteBufferWithInfo bbwi);

    /**
     * Called once after creating this buffer manager and before
     * it begins processing.
     */
    public void init(Message header);

    /**
     * Returns the mark/reset handler for this stream.
     */
    public MarkAndResetHandler getMarkAndResetHandler();

    /*
     * Signals that the processing be cancelled.
     */
    public void cancelProcessing(int requestId);

    /*
     * Close BufferManagerRead and perform any oustanding cleanup.
     */
    public void close(ByteBufferWithInfo bbwi);
}

⏎ com/sun/corba/se/impl/encoding/BufferManagerRead.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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