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/InvalidApplicationException.java

/*
 * Copyright (c) 1999, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.management;


/**
 * Thrown when an attempt is made to apply either of the following: A
 * subquery expression to an MBean or a qualified attribute expression
 * to an MBean of the wrong class.  This exception is used internally
 * by JMX during the evaluation of a query.  User code does not
 * usually see it.
 *
 * @since 1.5
 */
public class InvalidApplicationException extends Exception   {


    /* Serial version */
    private static final long serialVersionUID = -3048022274675537269L;

    /**
     * @serial The object representing the class of the MBean
     */
    private Object val;


    /**
     * Constructs an <CODE>InvalidApplicationException</CODE> with the specified <CODE>Object</CODE>.
     *
     * @param val the detail message of this exception.
     */
    public InvalidApplicationException(Object val) {
        this.val = val;
    }
}

⏎ javax/management/InvalidApplicationException.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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