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/IDLTypeOperations.java

/*
 * Copyright (c) 1999, 2001, 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;

/**
* The interface for <tt>IDLType</tt>.  For more information on
* Operations interfaces, see <a href="doc-files/generatedfiles.html#operations">
* "Generated Files: Operations files"</a>.
*/

/*
 tempout/org/omg/CORBA/IDLTypeOperations.java
 Generated by the IBM IDL-to-Java compiler, version 1.0
 from ../../Lib/ir.idl
 Thursday, February 25, 1999 2:11:23 o'clock PM PST
*/

/**
 * This interface must be implemented by all IDLType objects.
 * The IDLType is inherited by all IR objects that
 * represent IDL types, including interfaces, typedefs, and
 * anonymous types.
 * @see IDLType
 * @see IRObject
 * @see IRObjectOperations
 */

public interface IDLTypeOperations  extends org.omg.CORBA.IRObjectOperations
{
    /**
     * The type attribute describes the type defined by an object
     * derived from <code>IDLType</code>.
     * @return the <code>TypeCode</code> defined by this object.
     */
    org.omg.CORBA.TypeCode type ();
} // interface IDLTypeOperations

⏎ org/omg/CORBA/IDLTypeOperations.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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