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/copyobject/ObjectCopier.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.copyobject ;

/** Provides an interface for a variety of means to copy an arbitrary
 * object.  Any implementation of this interface must return an exact
 * copy of obj, preserving all aliasing across all objects reachable
 * from obj.  ReflectiveCopyException must be thrown if the implementation
 * cannot copy obj for some reason.  Note that a trivial implementation
 * of this interface is possible (always return obj), but this is often
 * not the desired implementation.
 */
public interface ObjectCopier {
    Object copy( Object obj ) throws ReflectiveCopyException ;
}

⏎ com/sun/corba/se/spi/copyobject/ObjectCopier.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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