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/IOP/TAG_ALTERNATE_IIOP_ADDRESS.java

package org.omg.IOP;


/**
* org/omg/IOP/TAG_ALTERNATE_IIOP_ADDRESS.java .
* Generated by the IDL-to-Java compiler (portable), version "3.2"
* from c:/re/workspace/8-2-build-windows-amd64-cygwin/jdk8u191/11896/corba/src/share/classes/org/omg/PortableInterceptor/IOP.idl
* Saturday, October 6, 2018 9:30:42 AM PDT
*/

public interface TAG_ALTERNATE_IIOP_ADDRESS
{

  /**
     * In cases where the same object key is used for more than one 
     * internet location, the following standard IOR Component is defined 
     * for support in IIOP version 1.2. 
     * <p>
     * The <code>TAG_ALTERNATE_IIOP_ADDRESS</code> component has an 
     * associated value of type:
     * <code>
     *   <pre>
     *     struct { 
     *         string HostID, 
     *         short Port 
     *     }; 
     *   </pre>
     * </code>
     * encoded as a CDR encapsulation. 
     * <p>
     * Zero or more instances of the <code>TAG_ALTERNATE_IIOP_ADDRESS</code> 
     * component type may be included in a version 1.2 
     * <code>TAG_INTERNET_IOP</code> Profile. Each of these alternative 
     * addresses may be used by the client orb, in addition to the host 
     * and port address expressed in the body of the Profile. In cases 
     * where one or more <code>TAG_ALTERNATE_IIOP_ADDRESS</code> components 
     * are present in a <code>TAG_INTERNET_IOP</code> Profile, no order of 
     * use is prescribed by Version 1.2 of IIOP.
     */
  public static final int value = (int)(3L);
}

⏎ org/omg/IOP/TAG_ALTERNATE_IIOP_ADDRESS.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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