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/ORBProxyOperations.java

package com.sun.corba.se.PortableActivationIDL;


/**
* com/sun/corba/se/PortableActivationIDL/ORBProxyOperations.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
*/


/** ORB callback interface, passed to Activator in registerORB method.
    */
public interface ORBProxyOperations 
{

  /** Method used to cause ORB to activate the named adapter, if possible.
	* This will cause the named POA to register itself with the activator as
	* a side effect.  This should always happen before this call can complete.
	* This method returns true if adapter activation succeeded, otherwise it
	* returns false.
	*/
  boolean activate_adapter (String[] name);
} // interface ORBProxyOperations

⏎ com/sun/corba/se/PortableActivationIDL/ORBProxyOperations.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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