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/LocatorOperations.java

package com.sun.corba.se.PortableActivationIDL;


/**
* com/sun/corba/se/PortableActivationIDL/LocatorOperations.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 LocatorOperations 
{

  /** locate server - returns the port with a specific type for all registered
	* ORBs of an active server.
	* Starts the server if it is not already running.
	*/
  com.sun.corba.se.PortableActivationIDL.LocatorPackage.ServerLocationPerType locateServer (String serverId, String endPoint) throws com.sun.corba.se.PortableActivationIDL.NoSuchEndPoint, com.sun.corba.se.PortableActivationIDL.ServerNotRegistered, com.sun.corba.se.PortableActivationIDL.ServerHeldDown;

  /** locate server - returns all ports registered with a specified ORB for
	* an active server
	* Starts the server if it is not already running.
	*/
  com.sun.corba.se.PortableActivationIDL.LocatorPackage.ServerLocationPerORB locateServerForORB (String serverId, String orbId) throws com.sun.corba.se.PortableActivationIDL.InvalidORBid, com.sun.corba.se.PortableActivationIDL.ServerNotRegistered, com.sun.corba.se.PortableActivationIDL.ServerHeldDown;

  /** get the port for the endpoint of the locator
	*/
  int getEndpoint (String endPointType) throws com.sun.corba.se.PortableActivationIDL.NoSuchEndPoint;

  /** Useful from external BadServerIdHandlers which need
	* to pick a particular port type.
	*/
  int getServerPortForType (com.sun.corba.se.PortableActivationIDL.LocatorPackage.ServerLocationPerORB location, String endPointType) throws com.sun.corba.se.PortableActivationIDL.NoSuchEndPoint;
} // interface LocatorOperations

⏎ com/sun/corba/se/PortableActivationIDL/LocatorOperations.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
Download 

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