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/ServantActivatorPOA.java

package org.omg.PortableServer;


/**
* org/omg/PortableServer/ServantActivatorPOA.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
*/


/**
	 * When the POA has the RETAIN policy it uses servant 
	 * managers that are ServantActivators. 
	 */
public abstract class ServantActivatorPOA extends org.omg.PortableServer.Servant
 implements org.omg.PortableServer.ServantActivatorOperations, org.omg.CORBA.portable.InvokeHandler
{

  // Constructors

  private static java.util.Hashtable _methods = new java.util.Hashtable ();
  static
  {
    _methods.put ("incarnate", new java.lang.Integer (0));
    _methods.put ("etherealize", new java.lang.Integer (1));
  }

  public org.omg.CORBA.portable.OutputStream _invoke (String $method,
                                org.omg.CORBA.portable.InputStream in,
                                org.omg.CORBA.portable.ResponseHandler $rh)
  {
    throw new org.omg.CORBA.BAD_OPERATION();
  } // _invoke

  // Type-specific CORBA::Object operations
  private static String[] __ids = {
    "IDL:omg.org/PortableServer/ServantActivator:2.3", 
    "IDL:omg.org/PortableServer/ServantManager:1.0"};

  public String[] _all_interfaces (org.omg.PortableServer.POA poa, byte[] objectId)
  {
    return (String[])__ids.clone ();
  }

  public ServantActivator _this() 
  {
    return ServantActivatorHelper.narrow(
    super._this_object());
  }

  public ServantActivator _this(org.omg.CORBA.ORB orb) 
  {
    return ServantActivatorHelper.narrow(
    super._this_object(orb));
  }


} // class ServantActivatorPOA

⏎ org/omg/PortableServer/ServantActivatorPOA.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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⇑⇑ FAQ for JDK (Java Development Kit)