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/Environment.java

/*
 * Copyright (c) 1996, 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;

/**
 * A container (holder) for an exception that is used in <code>Request</code>
 * operations to make exceptions available to the client.  An
 * <code>Environment</code> object is created with the <code>ORB</code>
 * method <code>create_environment</code>.
 *
 * @since   JDK1.2
 */

public abstract class Environment {

    /**
     * Retrieves the exception in this <code>Environment</code> object.
     *
     * @return                  the exception in this <code>Environment</code> object
     */

    public abstract java.lang.Exception exception();

    /**
     * Inserts the given exception into this <code>Environment</code> object.
     *
     * @param except            the exception to be set
     */

    public abstract void exception(java.lang.Exception except);

    /**
     * Clears this <code>Environment</code> object of its exception.
     */

    public abstract void clear();

}

⏎ org/omg/CORBA/Environment.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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