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/Message_1_0.java

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

package com.sun.corba.se.impl.protocol.giopmsgheaders;

import java.nio.ByteBuffer;
import org.omg.CORBA.INTERNAL;
import org.omg.CORBA.CompletionStatus;
import com.sun.corba.se.spi.ior.iiop.GIOPVersion;

import com.sun.corba.se.spi.logging.CORBALogDomains ;
import com.sun.corba.se.impl.logging.ORBUtilSystemException ;

/*
 * This implements the GIOP 1.0 Message header.
 *
 * @author Ram Jeyaraman 05/14/2000
 */

public class Message_1_0
        extends com.sun.corba.se.impl.protocol.giopmsgheaders.MessageBase {

    private static ORBUtilSystemException wrapper =
        ORBUtilSystemException.get( CORBALogDomains.RPC_PROTOCOL ) ;

    // Instance variables
    int magic = (int) 0;
    GIOPVersion GIOP_version = null;
    boolean byte_order = false;
    byte message_type = (byte) 0;
    int message_size = (int) 0;

    // Constructor

    Message_1_0() {
    }

    Message_1_0(int _magic, boolean _byte_order, byte _message_type,
            int _message_size) {
        magic = _magic;
        GIOP_version = GIOPVersion.V1_0;
        byte_order = _byte_order;
        message_type = _message_type;
        message_size = _message_size;
    }

    // Accessor methods

    public GIOPVersion getGIOPVersion() {
        return this.GIOP_version;
    }

    public int getType() {
        return this.message_type;
    }

    public int getSize() {
            return this.message_size;
    }

    public boolean isLittleEndian() {
        return this.byte_order;
    }

    public boolean moreFragmentsToFollow() {
        return false;
    }

    // Mutator methods

    public void setSize(ByteBuffer byteBuffer, int size) {
            this.message_size = size;

        //
        // Patch the size field in the header.
        //
            int patch = size - GIOPMessageHeaderLength;
        if (!isLittleEndian()) {
            byteBuffer.put(8,  (byte)((patch >>> 24) & 0xFF));
            byteBuffer.put(9,  (byte)((patch >>> 16) & 0xFF));
            byteBuffer.put(10, (byte)((patch >>> 8)  & 0xFF));
            byteBuffer.put(11, (byte)((patch >>> 0)  & 0xFF));
        } else {
            byteBuffer.put(8,  (byte)((patch >>> 0)  & 0xFF));
            byteBuffer.put(9,  (byte)((patch >>> 8)  & 0xFF));
            byteBuffer.put(10, (byte)((patch >>> 16) & 0xFF));
            byteBuffer.put(11, (byte)((patch >>> 24) & 0xFF));
        }
    }

    public FragmentMessage createFragmentMessage() {
        throw wrapper.fragmentationDisallowed(
            CompletionStatus.COMPLETED_MAYBE);
    }

    // IO methods

    // This should do nothing even if it is called. The Message Header already
    // is read off java.io.InputStream (not a CDRInputStream) by IIOPConnection
    // in order to choose the correct CDR Version, msg_type, and msg_size.
    // So, we would never need to read the Message Header off a CDRInputStream.
    public void read(org.omg.CORBA.portable.InputStream istream) {
        /*
        this.magic = istream.read_long();
        this.GIOP_version = (new GIOPVersion()).read(istream);
        this.byte_order = istream.read_boolean();
        this.message_type = istream.read_octet();
        this.message_size = istream.read_ulong();
        */
    }

    public void write(org.omg.CORBA.portable.OutputStream ostream) {
        ostream.write_long(this.magic);
        nullCheck(this.GIOP_version);
        this.GIOP_version.write(ostream);
        ostream.write_boolean(this.byte_order);
        ostream.write_octet(this.message_type);
        ostream.write_ulong(this.message_size);
    }

} // class Message_1_0

⏎ com/sun/corba/se/impl/protocol/giopmsgheaders/Message_1_0.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
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