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/threadpool/ThreadPoolManager.java

/*
 * Copyright (c) 2003, 2012, 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.threadpool;

import java.io.Closeable;

public interface ThreadPoolManager extends Closeable
{
    /**
    * This method will return an instance of the threadpool given a threadpoolId,
    * that can be used by any component in the app. server.
    *
    * @throws NoSuchThreadPoolException thrown when invalid threadpoolId is passed
    * as a parameter
    */
    public ThreadPool getThreadPool(String threadpoolId) throws NoSuchThreadPoolException;

    /**
    * This method will return an instance of the threadpool given a numeric threadpoolId.
    * This method will be used by the ORB to support the functionality of
    * dedicated threadpool for EJB beans
    *
    * @throws NoSuchThreadPoolException thrown when invalidnumericIdForThreadpool is passed
    * as a parameter
    */
    public ThreadPool getThreadPool(int numericIdForThreadpool) throws NoSuchThreadPoolException;

    /**
    * This method is used to return the numeric id of the threadpool, given a String
    * threadpoolId. This is used by the POA interceptors to add the numeric threadpool
    * Id, as a tagged component in the IOR. This is used to provide the functionality of
    * dedicated threadpool for EJB beans
    */
    public int  getThreadPoolNumericId(String threadpoolId);

    /**
    * Return a String Id for a numericId of a threadpool managed by the threadpool
    * manager
    */
    public String getThreadPoolStringId(int numericIdForThreadpool);

    /**
    * Returns the first instance of ThreadPool in the ThreadPoolManager
    */
    public ThreadPool getDefaultThreadPool();

    /**
     * Return an instance of ThreadPoolChooser based on the componentId that was
     * passed as argument
     */
    public ThreadPoolChooser getThreadPoolChooser(String componentId);

    /**
     * Return an instance of ThreadPoolChooser based on the componentIndex that was
     * passed as argument. This is added for improved performance so that the caller
     * does not have to pay the cost of computing hashcode for the componentId
     */
    public ThreadPoolChooser getThreadPoolChooser(int componentIndex);

    /**
     * Sets a ThreadPoolChooser for a particular componentId in the ThreadPoolManager. This
     * would enable any component to add a ThreadPoolChooser for their specific use
     */
    public void setThreadPoolChooser(String componentId, ThreadPoolChooser aThreadPoolChooser);

    /**
     * Gets the numeric index associated with the componentId specified for a
     * ThreadPoolChooser. This method would help the component call the more
     * efficient implementation i.e. getThreadPoolChooser(int componentIndex)
     */
    public int getThreadPoolChooserNumericId(String componentId);
}

// End of file.

⏎ com/sun/corba/se/spi/orbutil/threadpool/ThreadPoolManager.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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