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/ORBPackage/InvalidName.java

/*
 * Copyright (c) 1997, 2000, 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.ORBPackage;

/**
 * The <code>InvalidName</code> exception is raised when
 * <code>ORB.resolve_initial_references</code> is passed a name
 * for which there is no initial reference.
 *
 * @see org.omg.CORBA.ORB#resolve_initial_references(String)
 * @since   JDK1.2
 */

final public class InvalidName extends org.omg.CORBA.UserException {
    /**
     * Constructs an <code>InvalidName</code> exception with no reason message.
     */
    public InvalidName() {
        super();
    }

    /**
     * Constructs an <code>InvalidName</code> exception with the specified
     * reason message.
     * @param reason the String containing a reason message
     */
    public InvalidName(String reason) {
        super(reason);
    }
}

⏎ org/omg/CORBA/ORBPackage/InvalidName.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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