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/StructMember.java

/*
 * Copyright (c) 1997, 2001, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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/*
 * File: ./org/omg/CORBA/StructMember.java
 * From: ./ir.idl
 * Date: Fri Aug 28 16:03:31 1998
 *   By: idltojava Java IDL 1.2 Aug 11 1998 02:00:18
 */

package org.omg.CORBA;

/**
 * Describes a member of an IDL <code>struct</code> in the
 * Interface Repository, including
 * the  name of the <code>struct</code> member, the type of
 * the <code>struct</code> member, and
 * the typedef that represents the IDL type of the
 * <code>struct</code> member
 * described the <code>struct</code> member object.
 */
public final class StructMember implements org.omg.CORBA.portable.IDLEntity {

    //  instance variables

    /**
     * The name of the struct member described by
     * this <code>StructMember</code> object.
     * @serial
     */
    public String name;

    /**
     * The type of the struct member described by
     * this <code>StructMember</code> object.
     * @serial
     */
    public org.omg.CORBA.TypeCode type;

    /**
     * The typedef that represents the IDL type of the struct member described by
     * this <code>StructMember</code> object.
     * @serial
     */
    public org.omg.CORBA.IDLType type_def;
    //  constructors

    /**
     * Constructs a default <code>StructMember</code> object.
     */
    public StructMember() { }

    /**
     * Constructs a <code>StructMember</code> object initialized with the
     * given values.
     * @param __name a <code>String</code> object with the name of the struct
     *        member
     * @param __type a <code>TypeCode</code> object describing the type of the struct
     *        member
     * @param __type_def an <code>IDLType</code> object representing the IDL type
     *        of the struct member
     */
    public StructMember(String __name, org.omg.CORBA.TypeCode __type, org.omg.CORBA.IDLType __type_def) {
        name = __name;
        type = __type;
        type_def = __type_def;
    }
}

⏎ org/omg/CORBA/StructMember.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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