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 javax.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ javax/management/loading/PrivateMLet.java

/*
 * Copyright (c) 2002, 2007, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
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 *
 */

package javax.management.loading;

import java.net.URL;
import java.net.URLStreamHandlerFactory;

/**
 * An MLet that is not added to the {@link ClassLoaderRepository}.
 * This class acts exactly like its parent class, {@link MLet}, with
 * one exception.  When a PrivateMLet is registered in an MBean
 * server, it is not added to that MBean server's {@link
 * ClassLoaderRepository}.  This is true because this class implements
 * the interface {@link PrivateClassLoader}.
 *
 * @since 1.5
 */
public class PrivateMLet extends MLet implements PrivateClassLoader {
    private static final long serialVersionUID = 2503458973393711979L;

    /**
      * Constructs a new PrivateMLet for the specified URLs using the
      * default delegation parent ClassLoader.  The URLs will be
      * searched in the order specified for classes and resources
      * after first searching in the parent class loader.
      *
      * @param  urls  The URLs from which to load classes and resources.
      * @param  delegateToCLR  True if, when a class is not found in
      * either the parent ClassLoader or the URLs, the MLet should delegate
      * to its containing MBeanServer's {@link ClassLoaderRepository}.
      *
      */
    public PrivateMLet(URL[] urls, boolean delegateToCLR) {
        super(urls, delegateToCLR);
    }

    /**
      * Constructs a new PrivateMLet for the given URLs. The URLs will
      * be searched in the order specified for classes and resources
      * after first searching in the specified parent class loader.
      * The parent argument will be used as the parent class loader
      * for delegation.
      *
      * @param  urls  The URLs from which to load classes and resources.
      * @param  parent The parent class loader for delegation.
      * @param  delegateToCLR  True if, when a class is not found in
      * either the parent ClassLoader or the URLs, the MLet should delegate
      * to its containing MBeanServer's {@link ClassLoaderRepository}.
      *
      */
    public PrivateMLet(URL[] urls, ClassLoader parent, boolean delegateToCLR) {
        super(urls, parent, delegateToCLR);
    }

    /**
      * Constructs a new PrivateMLet for the specified URLs, parent
      * class loader, and URLStreamHandlerFactory. The parent argument
      * will be used as the parent class loader for delegation. The
      * factory argument will be used as the stream handler factory to
      * obtain protocol handlers when creating new URLs.
      *
      * @param  urls  The URLs from which to load classes and resources.
      * @param  parent The parent class loader for delegation.
      * @param  factory  The URLStreamHandlerFactory to use when creating URLs.
      * @param  delegateToCLR  True if, when a class is not found in
      * either the parent ClassLoader or the URLs, the MLet should delegate
      * to its containing MBeanServer's {@link ClassLoaderRepository}.
      *
      */
    public PrivateMLet(URL[] urls,
                       ClassLoader parent,
                       URLStreamHandlerFactory factory,
                       boolean delegateToCLR) {
        super(urls, parent, factory, delegateToCLR);
    }
}

⏎ javax/management/loading/PrivateMLet.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - org.* Package Source Code

⇐ JRE 8 rt.jar - java.* Package Source Code

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