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 com.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ com/sun/corba/se/PortableActivationIDL/ActivatorOperations.java

package com.sun.corba.se.PortableActivationIDL;


/**
* com/sun/corba/se/PortableActivationIDL/ActivatorOperations.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/com/sun/corba/se/PortableActivationIDL/activation.idl
* Saturday, October 6, 2018 9:30:40 AM PDT
*/

public interface ActivatorOperations 
{

  /** A new ORB started server registers itself with the Activator
	*/
  void registerServer (String serverId, com.sun.corba.se.PortableActivationIDL.ServerProxy serverObj) throws com.sun.corba.se.PortableActivationIDL.ServerNotRegistered;

  /** A server is shutting down that was started by this activator.
	* Complete termination of the server is detected by the death of the
	* process implementing the server.
	*/
  void serverGoingDown (String serverId);

  /** Called whenever an ORB instance is created.  This registers
	* the transport endpoints and the ORB proxy callback object.
	* Note that we cannot detect when an ORB shuts down, although
	* all of the POA shutdowns should still be reported.
	*/
  void registerORB (String serverId, String orbId, com.sun.corba.se.PortableActivationIDL.ORBProxy orb, com.sun.corba.se.PortableActivationIDL.EndPointInfo[] endPointInfo) throws com.sun.corba.se.PortableActivationIDL.ServerNotRegistered, com.sun.corba.se.PortableActivationIDL.NoSuchEndPoint, com.sun.corba.se.PortableActivationIDL.ORBAlreadyRegistered;

  /** Construct or find an ORBD object template corresponding to the 
	* server's object template and return it.  Called whenever a 
	* persistent POA is created.
	*/
  org.omg.PortableInterceptor.ObjectReferenceTemplate registerPOA (String serverId, String orbId, org.omg.PortableInterceptor.ObjectReferenceTemplate poaTemplate);

  /** Called whenever a POA is destroyed.
	*/
  void poaDestroyed (String serverId, String orbId, org.omg.PortableInterceptor.ObjectReferenceTemplate poaTemplate);

  /** If the server is not running, start it up.  This is allowed
	* whether or not the server has been installed.
	*/
  void activate (String serverId) throws com.sun.corba.se.PortableActivationIDL.ServerAlreadyActive, com.sun.corba.se.PortableActivationIDL.ServerNotRegistered, com.sun.corba.se.PortableActivationIDL.ServerHeldDown;

  /** If the server is running, shut it down
	*/
  void shutdown (String serverId) throws com.sun.corba.se.PortableActivationIDL.ServerNotActive, com.sun.corba.se.PortableActivationIDL.ServerNotRegistered;

  /** Invoke the server install hook.  If the server is not 
	* currently running, this method will activate it.
	*/
  void install (String serverId) throws com.sun.corba.se.PortableActivationIDL.ServerNotRegistered, com.sun.corba.se.PortableActivationIDL.ServerHeldDown, com.sun.corba.se.PortableActivationIDL.ServerAlreadyInstalled;

  /** Invoke the server uninstall hook.  If the server is not
	* currently running, this method will activate it.
	* After this hook completes, the server may still be running.
	*/
  void uninstall (String serverId) throws com.sun.corba.se.PortableActivationIDL.ServerNotRegistered, com.sun.corba.se.PortableActivationIDL.ServerHeldDown, com.sun.corba.se.PortableActivationIDL.ServerAlreadyUninstalled;

  /** list active servers
	*/
  String[] getActiveServers ();

  /** list all registered ORBs for a server
	*/
  String[] getORBNames (String serverId) throws com.sun.corba.se.PortableActivationIDL.ServerNotRegistered;

  /** Find the server template that corresponds to the ORBD's
	* adapter id.
	*/
  org.omg.PortableInterceptor.ObjectReferenceTemplate lookupPOATemplate (String serverId, String orbId, String[] orbAdapterName);
} // interface ActivatorOperations

⏎ com/sun/corba/se/PortableActivationIDL/ActivatorOperations.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
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