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/POAManagerOperations.java

package org.omg.PortableServer;


/**
* org/omg/PortableServer/POAManagerOperations.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
*/


/**
	 * Each POA object has an associated POAManager object. 
	 * A POA manager may be associated with one or more 
	 * POA objects. A POA manager encapsulates the processing 
	 * state of the POAs it is associated with.
	 */
public interface POAManagerOperations 
{

  /**
	 * This operation changes the state of the POA manager 
	 * to active, causing associated POAs to start processing
	 * requests.
	 * @exception AdapterInactive is raised if the operation is
	 *            invoked on the POAManager in inactive state.
	 */
  void activate () throws org.omg.PortableServer.POAManagerPackage.AdapterInactive;

  /**
	 * This operation changes the state of the POA manager 
	 * to holding, causing associated POAs to queue incoming
	 * requests.
	 * @param wait_for_completion if FALSE, the operation 
	 *            returns immediately after changing state.  
	 *            If TRUE, it waits for all active requests 
	 *            to complete. 
	 * @exception AdapterInactive is raised if the operation is
	 *            invoked on the POAManager in inactive state.
	 */
  void hold_requests (boolean wait_for_completion) throws org.omg.PortableServer.POAManagerPackage.AdapterInactive;

  /**
	 * This operation changes the state of the POA manager 
	 * to discarding. This causes associated POAs to discard
	 * incoming requests.
	 * @param wait_for_completion if FALSE, the operation 
	 *            returns immediately after changing state.  
	 *            If TRUE, it waits for all active requests 
	 *            to complete. 
	 * @exception AdapterInactive is raised if the operation is
	 *            invoked on the POAManager in inactive state.
	 */
  void discard_requests (boolean wait_for_completion) throws org.omg.PortableServer.POAManagerPackage.AdapterInactive;

  /**
	 * This operation changes the state of the POA manager 
	 * to inactive, causing associated POAs to reject the
	 * requests that have not begun executing as well as
	 * as any new requests.
	 * @param etherealize_objects a flag to indicate whether
	 *        to invoke the etherealize operation of the
	 *        associated servant manager for all active 
	 *        objects.
	 * @param wait_for_completion if FALSE, the operation 
	 *            returns immediately after changing state.  
	 *            If TRUE, it waits for all active requests 
	 *            to complete. 
	 * @exception AdapterInactive is raised if the operation is
	 *            invoked on the POAManager in inactive state.
	 */
  void deactivate (boolean etherealize_objects, boolean wait_for_completion) throws org.omg.PortableServer.POAManagerPackage.AdapterInactive;

  /**
	 * This operation returns the state of the POA manager.
	 */
  org.omg.PortableServer.POAManagerPackage.State get_state ();
} // interface POAManagerOperations

⏎ org/omg/PortableServer/POAManagerOperations.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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