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/defaults/SnmpProperties.java

/*
 * Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 *
 *
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 */

package com.sun.jmx.snmp.defaults;

// java import
//
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.IOException;
import java.util.Properties;
import java.util.Enumeration;

/**
 * This class reads a file containing the property list defined for Java DMK
 * and adds all the read properties to the list of system properties.
 *
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 *
 * @since 1.5
 */
public class SnmpProperties {

    // private constructor defined to "hide" the default public constructor
    private SnmpProperties() {
    }

    // PUBLIC STATIC METHODS
    //----------------------

    /**
     * Reads the Java DMK property list from a file and
     * adds the read properties as system properties.
     */
    public static void load(String file) throws IOException {
        Properties props = new Properties();
        InputStream is = new FileInputStream(file);
        props.load(is);
        is.close();
        for (final Enumeration<?> e = props.keys(); e.hasMoreElements() ; ) {
            final String key = (String) e.nextElement();
            System.setProperty(key,props.getProperty(key));
        }
    }

    // PUBLIC STATIC VARIABLES
    //------------------------

    /**
     * References the property that specifies the directory where
     * the native libraries will be stored before the MLet Service
     * loads them into memory.
     * <p>
     * Property Name: <B>jmx.mlet.library.dir</B>
     */
    public static final String MLET_LIB_DIR = "jmx.mlet.library.dir";

    /**
     * References the property that specifies the ACL file
     * used by the SNMP protocol adaptor.
     * <p>
     * Property Name: <B>jdmk.acl.file</B>
     */
    public static final String ACL_FILE = "jdmk.acl.file";

    /**
     * References the property that specifies the Security file
     * used by the SNMP protocol adaptor.
     * <p>
     * Property Name: <B>jdmk.security.file</B>
     */
    public static final String SECURITY_FILE = "jdmk.security.file";

    /**
     * References the property that specifies the User ACL file
     * used by the SNMP protocol adaptor.
     * <p>
     * Property Name: <B>jdmk.uacl.file</B>
     */
    public static final String UACL_FILE = "jdmk.uacl.file";

    /**
     * References the property that specifies the default mib_core file
     * used by the mibgen compiler.
     * <p>
     * Property Name: <B>mibcore.file</B>
     */
    public static final String MIB_CORE_FILE = "mibcore.file";

    /**
     * References the property that specifies the full name of the JMX
     * specification implemented by this product.
     * <p>
     * Property Name: <B>jmx.specification.name</B>
     */
     public static final String JMX_SPEC_NAME = "jmx.specification.name";

    /**
     * References the property that specifies the version of the JMX
     * specification implemented by this product.
     * <p>
     * Property Name: <B>jmx.specification.version</B>
     */
     public static final String JMX_SPEC_VERSION = "jmx.specification.version";

    /**
     * References the property that specifies the vendor of the JMX
     * specification implemented by this product.
     * <p>
     * Property Name: <B>jmx.specification.vendor</B>
     */
     public static final String JMX_SPEC_VENDOR = "jmx.specification.vendor";

    /**
     * References the property that specifies the full name of this product
     * implementing the  JMX specification.
     * <p>
     * Property Name: <B>jmx.implementation.name</B>
     */
    public static final String JMX_IMPL_NAME = "jmx.implementation.name";

    /**
     * References the property that specifies the name of the vendor of this product
     * implementing the  JMX specification.
     * <p>
     * Property Name: <B>jmx.implementation.vendor</B>
     */
    public static final String JMX_IMPL_VENDOR = "jmx.implementation.vendor";

    /**
     * References the property that specifies the version of this product
     * implementing the  JMX specification.
     * <p>
     * Property Name: <B>jmx.implementation.version</B>
     */
    public static final String JMX_IMPL_VERSION = "jmx.implementation.version";

    /**
     * References the property that specifies the SSL cipher suites to
     * be enabled by the HTTP/SSL connector.
     * <p>
     * Property Name: <B>jdmk.ssl.cipher.suite.</B>
     * <p>
     * The list of SSL cipher suites is specified in the format:
     * <p>
     * <DD><B>jdmk.ssl.cipher.suite.</B>&lt;n&gt;<B>=</B>&lt;cipher suite name&gt;</DD>
     * <p>
     * For example:
     * <p>
     * <DD>jdmk.ssl.cipher.suite.1=SSL_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA</DD>
     * <DD>jdmk.ssl.cipher.suite.2=SSL_RSA_EXPORT_WITH_RC4_40_MD5</DD>
     * <DD>. . .</DD>
     */
    public static final String SSL_CIPHER_SUITE = "jdmk.ssl.cipher.suite.";
}

⏎ com/sun/jmx/snmp/defaults/SnmpProperties.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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