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/remote/JMXProviderException.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.remote;

import java.io.IOException;

/**
 * <p>Exception thrown by {@link JMXConnectorFactory} and
 * {@link JMXConnectorServerFactory} when a provider exists for
 * the required protocol but cannot be used for some reason.</p>
 *
 * @see JMXConnectorFactory#newJMXConnector
 * @see JMXConnectorServerFactory#newJMXConnectorServer
 * @since 1.5
 */
public class JMXProviderException extends IOException {

    private static final long serialVersionUID = -3166703627550447198L;

    /**
     * <p>Constructs a <code>JMXProviderException</code> with no
     * specified detail message.</p>
     */
    public JMXProviderException() {
    }

    /**
     * <p>Constructs a <code>JMXProviderException</code> with the
     * specified detail message.</p>
     *
     * @param message the detail message
     */
    public JMXProviderException(String message) {
        super(message);
    }

    /**
     * <p>Constructs a <code>JMXProviderException</code> with the
     * specified detail message and nested exception.</p>
     *
     * @param message the detail message
     * @param cause the nested exception
     */
    public JMXProviderException(String message, Throwable cause) {
        super(message);
        this.cause = cause;
    }

    public Throwable getCause() {
        return cause;
    }

    /**
     * @serial An exception that caused this exception to be thrown.
     *         This field may be null.
     * @see #getCause()
     **/
    private Throwable cause = null;
}

⏎ javax/management/remote/JMXProviderException.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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