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/jmx/snmp/SnmpPduPacket.java

/*
 *
 * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
// Copyright (c) 1995-96 by Cisco Systems, Inc.

package com.sun.jmx.snmp;

import java.io.Serializable;
import java.net.InetAddress;

/**
 * Is the fully decoded representation of an SNMP packet.
 * <P>
 * You will not usually need to use this class, except if you
 * decide to implement your own
 * {@link com.sun.jmx.snmp.SnmpPduFactory SnmpPduFactory} object.
 * <P>
 * Classes are derived from <CODE>SnmpPduPacket</CODE> to
 * represent the different forms of SNMP packets
 * ({@link com.sun.jmx.snmp.SnmpPduRequest SnmpPduRequest},
 * {@link com.sun.jmx.snmp.SnmpPduTrap SnmpPduTrap},
 * {@link com.sun.jmx.snmp.SnmpPduBulk SnmpPduBulk}).
 * <BR>The <CODE>SnmpPduPacket</CODE> class defines the attributes
 * common to every form of SNMP packets.
 *
 *
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 * @see SnmpMessage
 * @see SnmpPduFactory
 *
 */

public abstract class SnmpPduPacket extends SnmpPdu implements Serializable {
    /**
     * The pdu community string.
     */
    public byte[] community ;
}

⏎ com/sun/jmx/snmp/SnmpPduPacket.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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