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/SnmpValue.java

/*
 * Copyright (c) 1997, 2007, 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 java.io.Serializable;

/**
 * Is an abstract representation of an SNMP Value.
 * All classes provided for dealing with SNMP types should derive from this
 * class.
 *
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 */

public abstract class SnmpValue implements Cloneable, Serializable, SnmpDataTypeEnums {

    /**
     * Returns a <CODE>String</CODE> form containing ASN.1 tagging information.
     * @return The <CODE>String</CODE> form.
     */
    public String toAsn1String() {
        return "[" + getTypeName() + "] " + toString();
    }

    /**
     * Returns the value encoded as an OID.
     * The method is particularly useful when dealing with indexed table made of
     * several SNMP variables.
     * @return The value encoded as an OID.
     */
    public abstract SnmpOid toOid() ;

    /**
     * Returns a textual description of the object.
     * @return ASN.1 textual description.
     */
    public abstract String getTypeName() ;

    /**
     * Same as clone, but you cannot perform cloning using this object because
     * clone is protected. This method should call <CODE>clone()</CODE>.
     * @return The <CODE>SnmpValue</CODE> clone.
     */
    public abstract SnmpValue duplicate() ;

    /**
     * This method returns <CODE>false</CODE> by default and is redefined
     * in the {@link com.sun.jmx.snmp.SnmpNull} class.
     */
    public boolean isNoSuchObjectValue() {
        return false;
    }

    /**
     * This method returns <CODE>false</CODE> by default and is redefined
     * in the {@link com.sun.jmx.snmp.SnmpNull} class.
     */
    public boolean isNoSuchInstanceValue() {
        return false;
    }

    /**
     * This method returns <CODE>false</CODE> by default and is redefined
     * in the {@link com.sun.jmx.snmp.SnmpNull} class.
     */
    public boolean isEndOfMibViewValue() {
        return false;
    }
}

⏎ com/sun/jmx/snmp/SnmpValue.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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