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/spi/orbutil/fsm/Action.java

/*
 * Copyright (c) 2002, 2003, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package com.sun.corba.se.spi.orbutil.fsm;

/**
 * Description goes here
 *
 * @author Ken Cavanaugh
 */
public interface Action
{
        /** Called by the state engine to perform an action
        * before a state transition takes place.  The FSM is
        * passed so that the Action may set the next state in
        * cases when that is required.  FSM and Input together
        * allow actions to be written that depend on the state and
        * input, but this should generally be avoided, as the
        * reason for a state machine in the first place is to cleanly
        * separate the actions and control flow.   Note that an
        * action should complete in a timely manner.  If the state machine
        * is used for concurrency control with multiple threads, the
        * action must not allow multiple threads to run simultaneously
        * in the state machine, as the state could be corrupted.
        * Any exception thrown by the Action for the transition
        * will be propagated to doIt.
        * @param FSM fsm is the state machine causing this action.
        * @param Input in is the input that caused the transition.
        */
        public void doIt( FSM fsm, Input in ) ;
}

// end of Action.java

⏎ com/sun/corba/se/spi/orbutil/fsm/Action.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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