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/awt/ItemSelectable.java

/*
 * Copyright (c) 1996, 2000, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.awt;

import java.awt.event.*;

/**
 * The interface for objects which contain a set of items for
 * which zero or more can be selected.
 *
 * @author Amy Fowler
 */

public interface ItemSelectable {

    /**
     * Returns the selected items or <code>null</code> if no
     * items are selected.
     */
    public Object[] getSelectedObjects();

    /**
     * Adds a listener to receive item events when the state of an item is
     * changed by the user. Item events are not sent when an item's
     * state is set programmatically.  If <code>l</code> is
     * <code>null</code>, no exception is thrown and no action is performed.
     *
     * @param    l the listener to receive events
     * @see ItemEvent
     */
    public void addItemListener(ItemListener l);

    /**
     * Removes an item listener.
     * If <code>l</code> is <code>null</code>,
     * no exception is thrown and no action is performed.
     *
     * @param   l the listener being removed
     * @see ItemEvent
     */
    public void removeItemListener(ItemListener l);
}

⏎ java/awt/ItemSelectable.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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