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/jmx/snmp/tasks/TaskServer.java

// NPCTE fix for bugId 4510777, esc 532372, MR October 2001
// file TaskServer.java created for this bug fix

/*
 * 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.jmx.snmp.tasks;

/**
 * This interface is implemented by objects that are able to execute
 * tasks. Whether the task is executed in the client thread or in another
 * thread depends on the TaskServer implementation.
 *
 * <p><b>This API is a Sun Microsystems internal API  and is subject
 * to change without notice.</b></p>
 * @see com.sun.jmx.snmp.tasks.Task
 *
 * @since 1.5
 **/
public interface TaskServer {
    /**
     * Submit a task to be executed.
     * Once a task is submitted, it is guaranteed that either
     * {@link com.sun.jmx.snmp.tasks.Task#run() task.run()} or
     * {@link com.sun.jmx.snmp.tasks.Task#cancel() task.cancel()} will be called.
     * <p>Whether the task is executed in the client thread (e.g.
     * <code>public void submitTask(Task task) { task.run(); }</code>) or in
     * another thread (e.g. <code>
     * public void submitTask(Task task) { new Thrad(task).start(); }</code>)
     * depends on the TaskServer implementation.
     * @param task The task to be executed.
     **/
    public void submitTask(Task task);
}

⏎ com/sun/jmx/snmp/tasks/TaskServer.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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