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

⏎ org/omg/CORBA/portable/ApplicationException.java

/*
 * Copyright (c) 1998, 1999, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package org.omg.CORBA.portable;

/**
This class is used for reporting application level exceptions between ORBs and stubs.
*/

public class ApplicationException extends Exception {
    /**
     * Constructs an ApplicationException from the CORBA repository ID of the exception
     * and an input stream from which the exception data can be read as its parameters.
     * @param id the repository id of the user exception
     * @param ins the stream which contains the user exception data
     */
    public ApplicationException(String id,
                                InputStream ins) {
        this.id = id;
        this.ins = ins;
    }

    /**
     * Returns the CORBA repository ID of the exception
     * without removing it from the exceptions input stream.
     * @return The CORBA repository ID of this exception
     */
    public String getId() {
        return id;
    }

    /**
     * Returns the input stream from which the exception data can be read as its parameters.
     * @return The stream which contains the user exception data
     */
    public InputStream getInputStream() {
        return ins;
    }

    private String id;
    private InputStream ins;
}

⏎ org/omg/CORBA/portable/ApplicationException.java

Or download all of them as a single archive file:

File name: jre-rt-org-1.8.0_191-src.zip
File size: 951125 bytes
Release date: 2018-10-28
Download 

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

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

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