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/impl/orbutil/concurrent/SyncUtil.java

/*
 * Copyright (c) 2001, 2002, 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.impl.orbutil.concurrent;

import com.sun.corba.se.impl.orbutil.concurrent.Sync ;

public class SyncUtil {
    private SyncUtil() {}

    /** Method to acquire a Sync without ever throwing an
    * InterruptedException.  Useful when a mutex is being
    * used in place of Java synchronization.
    */
    public static void acquire( Sync sync )
    {
        boolean held = false ;
        while (!held) {
            try {
                sync.acquire() ;
                held = true ;
            } catch (InterruptedException exc) {
                held = false ;
            }
        }
    }
}

⏎ com/sun/corba/se/impl/orbutil/concurrent/SyncUtil.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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