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/PortableServer/Current.java

package org.omg.PortableServer;


/**
* org/omg/PortableServer/Current.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/PortableServer/poa.idl
* Saturday, October 6, 2018 9:30:42 AM PDT
*/


/**
	 * The PortableServer::Current interface, derived from 
	 * CORBA::Current, provides method implementations with 
	 * access to the identity of the object on which the 
	 * method was invoked. The Current interface is provided 
	 * to support servants that implement multiple objects, 
	 * but can be used within the context of POA-dispatched 
	 * method invocations on any servant. To provide location 
	 * transparency, ORBs are required to support use of 
	 * Current in the context of both locally and remotely 
	 * invoked operations. An instance of Current can be 
	 * obtained by the application by issuing the 
	 * CORBA::ORB::resolve_initial_references("POACurrent") 
	 * operation. Thereafter, it can be used within the 
	 * context of a method dispatched by the POA to obtain 
	 * the POA and ObjectId that identify the object on 
	 * which that operation was invoked.
	 */
public interface Current extends CurrentOperations, org.omg.CORBA.Current, org.omg.CORBA.portable.IDLEntity 
{
} // interface Current

⏎ org/omg/PortableServer/Current.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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