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/ValueBase.java

/*
 * Copyright (c) 1999, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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/*
 * Licensed Materials - Property of IBM
 * RMI-IIOP v1.0
 * Copyright IBM Corp. 1998 1999  All Rights Reserved
 *
 */

package org.omg.CORBA.portable;
/**
 * The generated Java classes corresponding to valuetype IDL types
 * implement this interface. In other words, the Java mapping of
 * valuetype objects implement the ValueBase interface. The generated
 * Java class for valuetype's shall provide an implementation of the
 * ValueBase interface for the corresponding value type.
 * For value types that are streamable (i.e. non-custom),
 * the generated Java class shall also provide an implementation
 * for the org.omg.CORBA.portable.Streamable interface.
 * (CORBA::ValueBase is mapped to java.io.Serializable.)
 */
public interface ValueBase extends IDLEntity {
    /**
     * Provides truncatable repository ids.
     * @return a String array--list of truncatable repository ids.
     */
    String[] _truncatable_ids();
}

⏎ org/omg/CORBA/portable/ValueBase.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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