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/SnmpEngineFactory.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.jmx.snmp;

/**
 * This <CODE>SnmpEngineFactory</CODE> is instantiating an <CODE>SnmpEngine</CODE> containing :
 * <ul>
 * <li> Message Processing Sub System + V1, V2 et V3 Message Processing Models</li>
 * <li> Security Sub System + User based Security Model (Id 3)</li>
 * <li> Access Control Sub System + Ip Acl + User based Access Control Model. See <CODE> IpAcl </CODE> and <CODE> UserAcl </CODE>.</li>
 * </ul>
 *
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 * @since 1.5
 */
public interface SnmpEngineFactory {
    /**
     * The engine instantiation method.
     * @param p The parameters used to instantiate a new engine.
     * @throws IllegalArgumentException Throwed if one of the configuration file file doesn't exist (Acl files, security file).
     * @return The newly created SnmpEngine.
     */
    public SnmpEngine createEngine(SnmpEngineParameters p);

    /**
     * The engine instantiation method.
     * @param p The parameters used to instantiate a new engine.
     * @param ipacl The Ip ACL to pass to the Access Control Model.
     * @throws IllegalArgumentException Throwed if one of the configuration
     *         file file doesn't exist (Acl files, security file).
     * @return The newly created SnmpEngine.
     */
    public SnmpEngine createEngine(SnmpEngineParameters p,
                                   InetAddressAcl ipacl);
}

⏎ com/sun/jmx/snmp/SnmpEngineFactory.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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