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 java.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ java/beans/Visibility.java

/*
 * Copyright (c) 1996, 1998, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package java.beans;

/**
 * Under some circumstances a bean may be run on servers where a GUI
 * is not available.  This interface can be used to query a bean to
 * determine whether it absolutely needs a gui, and to advise the
 * bean whether a GUI is available.
 * <p>
 * This interface is for expert developers, and is not needed
 * for normal simple beans.  To avoid confusing end-users we
 * avoid using getXXX setXXX design patterns for these methods.
 */

public interface Visibility {

    /**
     * Determines whether this bean needs a GUI.
     *
     * @return True if the bean absolutely needs a GUI available in
     *          order to get its work done.
     */
    boolean needsGui();

    /**
     * This method instructs the bean that it should not use the Gui.
     */
    void dontUseGui();

    /**
     * This method instructs the bean that it is OK to use the Gui.
     */
    void okToUseGui();

    /**
     * Determines whether this bean is avoiding using a GUI.
     *
     * @return true if the bean is currently avoiding use of the Gui.
     *   e.g. due to a call on dontUseGui().
     */
    boolean avoidingGui();

}

⏎ java/beans/Visibility.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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