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/remote/util/ClassLogger.java

/*
 * Copyright (c) 2003, 2008, 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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 *
 *
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 *
 *
 */

package com.sun.jmx.remote.util;

import java.util.logging.Logger;

public class ClassLogger {

    private static final boolean ok;
    private final String className;
    private final Logger logger;

    static {
        /* We attempt to work even if we are running in J2SE 1.3, where
           there is no java.util.logging.  The technique we use here is
           not strictly portable, but it does work with Sun's J2SE 1.3
           at least.  This is just a best effort: the Right Thing is for
           people to use at least J2SE 1.4.  */
        boolean loaded = false;
        try {
            Class<?> c = java.util.logging.Logger.class;
            loaded = true;
        } catch (Error e) {
            // OK.
            // java.util.logger package is not available in this jvm.
        }
        ok = loaded;
    }

    public ClassLogger(String subsystem, String className) {
        if (ok)
            logger = Logger.getLogger(subsystem);
        else
            logger = null;
        this.className = className;
    }

    public final boolean traceOn() {
        return finerOn();
    }

    public final boolean debugOn() {
        return finestOn();
    }

    public final boolean warningOn() {
        return ok && logger.isLoggable(java.util.logging.Level.WARNING);
    }

    public final boolean infoOn() {
        return ok && logger.isLoggable(java.util.logging.Level.INFO);
    }

    public final boolean configOn() {
        return ok && logger.isLoggable(java.util.logging.Level.CONFIG);
    }

    public final boolean fineOn() {
        return ok && logger.isLoggable(java.util.logging.Level.FINE);
    }

    public final boolean finerOn() {
        return ok && logger.isLoggable(java.util.logging.Level.FINER);
    }

    public final boolean finestOn() {
        return ok && logger.isLoggable(java.util.logging.Level.FINEST);
    }

    public final void debug(String func, String msg) {
        finest(func,msg);
    }

    public final void debug(String func, Throwable t) {
        finest(func,t);
    }

    public final void debug(String func, String msg, Throwable t) {
        finest(func,msg,t);
    }

    public final void trace(String func, String msg) {
        finer(func,msg);
    }

    public final void trace(String func, Throwable t) {
        finer(func,t);
    }

    public final void trace(String func, String msg, Throwable t) {
        finer(func,msg,t);
    }

    public final void error(String func, String msg) {
        severe(func,msg);
    }

    public final void error(String func, Throwable t) {
        severe(func,t);
    }

    public final void error(String func, String msg, Throwable t) {
        severe(func,msg,t);
    }

    public final void finest(String func, String msg) {
        if (ok)
            logger.logp(java.util.logging.Level.FINEST, className, func, msg);
    }

    public final void finest(String func, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.FINEST, className, func,
                        t.toString(), t);
    }

    public final void finest(String func, String msg, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.FINEST, className, func, msg,
                        t);
    }

    public final void finer(String func, String msg) {
        if (ok)
            logger.logp(java.util.logging.Level.FINER, className, func, msg);
    }

    public final void finer(String func, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.FINER, className, func,
                        t.toString(), t);
    }

    public final void finer(String func, String msg, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.FINER, className, func, msg,t);
    }

    public final void fine(String func, String msg) {
        if (ok)
            logger.logp(java.util.logging.Level.FINE, className, func, msg);
    }

    public final void fine(String func, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.FINE, className, func,
                        t.toString(), t);
    }

    public final void fine(String func, String msg, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.FINE, className, func, msg,
                        t);
    }

    public final void config(String func, String msg) {
        if (ok)
            logger.logp(java.util.logging.Level.CONFIG, className, func, msg);
    }

    public final void config(String func, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.CONFIG, className, func,
                        t.toString(), t);
    }

    public final void config(String func, String msg, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.CONFIG, className, func, msg,
                        t);
    }

    public final void info(String func, String msg) {
        if (ok)
            logger.logp(java.util.logging.Level.INFO, className, func, msg);
    }

    public final void info(String func, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.INFO, className, func,
                        t.toString(), t);
    }

    public final void info(String func, String msg, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.INFO, className, func, msg,
                        t);
    }

    public final void warning(String func, String msg) {
        if (ok)
            logger.logp(java.util.logging.Level.WARNING, className, func, msg);
    }

    public final void warning(String func, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.WARNING, className, func,
                        t.toString(), t);
    }

    public final void warning(String func, String msg, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.WARNING, className, func, msg,
                        t);
    }

    public final void severe(String func, String msg) {
        if (ok)
            logger.logp(java.util.logging.Level.SEVERE, className, func, msg);
    }

    public final void severe(String func, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.SEVERE, className, func,
                        t.toString(), t);
    }

    public final void severe(String func, String msg, Throwable t) {
        if (ok)
            logger.logp(java.util.logging.Level.SEVERE, className, func, msg,
                        t);
    }
}

⏎ com/sun/jmx/remote/util/ClassLogger.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
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