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/SnmpParams.java

/*
 * Copyright (c) 2001, 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;

import com.sun.jmx.snmp.SnmpDefinitions;

/**
 * This class is the base class of all parameters that are used when making SNMP requests to an <CODE>SnmpPeer</CODE>.
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 * @since 1.5
 */
public abstract class SnmpParams implements SnmpDefinitions {
    private int protocolVersion = snmpVersionOne;
    SnmpParams(int version) {
        protocolVersion = version;
    }

    SnmpParams() {}
    /**
     * Checks whether parameters are in place for an SNMP <CODE>set</CODE> operation.
     * @return <CODE>true</CODE> if parameters are in place, <CODE>false</CODE> otherwise.
     */
    public abstract boolean allowSnmpSets();
    /**
     * Returns the version of the protocol to use.
     * The returned value is:
     * <UL>
     * <LI>{@link com.sun.jmx.snmp.SnmpDefinitions#snmpVersionOne snmpVersionOne} if the protocol is SNMPv1
     * <LI>{@link com.sun.jmx.snmp.SnmpDefinitions#snmpVersionTwo snmpVersionTwo} if the protocol is SNMPv2
     * <LI>{@link com.sun.jmx.snmp.SnmpDefinitions#snmpVersionThree snmpVersionThree} if the protocol is SNMPv3
     * </UL>
     * @return The version of the protocol to use.
     */
    public int getProtocolVersion() {
        return protocolVersion ;
    }

    /**
     * Sets the version of the protocol to be used.
     * The version should be identified using the definitions
     * contained in
     * {@link com.sun.jmx.snmp.SnmpDefinitions SnmpDefinitions}.
     * <BR>For instance if you wish to use SNMPv2, you can call the method as follows:
     * <BLOCKQUOTE><PRE>
     * setProtocolVersion(SnmpDefinitions.snmpVersionTwo);
     * </PRE></BLOCKQUOTE>
     * @param protocolversion The version of the protocol to be used.
     */

    public void setProtocolVersion(int protocolversion) {
        this.protocolVersion = protocolversion ;
    }
}

⏎ com/sun/jmx/snmp/SnmpParams.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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