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/JMXServerErrorException.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;

// imports for javadoc
import javax.management.MBeanServer;

/**
 * Exception thrown as the result of a remote {@link MBeanServer}
 * method invocation when an <code>Error</code> is thrown while
 * processing the invocation in the remote MBean server.  A
 * <code>JMXServerErrorException</code> instance contains the original
 * <code>Error</code> that occurred as its cause.
 *
 * @see java.rmi.ServerError
 * @since 1.5
 */
public class JMXServerErrorException extends IOException {

    private static final long serialVersionUID = 3996732239558744666L;

    /**
     * Constructs a <code>JMXServerErrorException</code> with the specified
     * detail message and nested error.
     *
     * @param s the detail message.
     * @param err the nested error.  An instance of this class can be
     * constructed where this parameter is null, but the standard
     * connectors will never do so.
     */
    public JMXServerErrorException(String s, Error err) {
        super(s);
        cause = err;
    }

    public Throwable getCause() {
        return cause;
    }

    /**
     * @serial An {@link Error} that caused this exception to be thrown.
     * @see #getCause()
     **/
    private final Error cause;
}

⏎ javax/management/remote/JMXServerErrorException.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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