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/ThreadPoolChooser.java

/*
 * Copyright (c) 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.threadpool;


public interface ThreadPoolChooser
{
    /**
     * This method is used to return an instance of ThreadPool based on the
     * strategy/policy implemented in the ThreadPoolChooser from the set of
     * ThreadPools allowed to be used by the ORB. Typically, the set of
     * ThreadPools would be specified by passing the threadpool-ids
     * configured in the ORB element of the domain.xml of the appserver.
     */
    public ThreadPool getThreadPool();

    /**
     * This method is used to return an instance of ThreadPool that is obtained
     * by using the id argument passed to it. This method will be used in
     * situations where the threadpool id is known to the caller e.g. by the
     * connection object or looking at the high order bits of the request id
     */
    public ThreadPool getThreadPool(int id);

    /**
     * This method is a convenience method to see what threadpool-ids are being
     * used by the ThreadPoolChooser
     */
    public String[] getThreadPoolIds();
}

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