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

⏎ javax/swing/colorchooser/ColorSelectionModel.java

/*
 * Copyright (c) 1998, 2001, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.swing.colorchooser;

import javax.swing.*;
import javax.swing.event.*;
import java.awt.Color;

/**
 * A model that supports selecting a <code>Color</code>.
 *
 * @author Steve Wilson
 *
 * @see java.awt.Color
 */
public interface ColorSelectionModel {
    /**
     * Returns the selected <code>Color</code> which should be
     * non-<code>null</code>.
     *
     * @return  the selected <code>Color</code>
     * @see     #setSelectedColor
     */
    Color getSelectedColor();

    /**
     * Sets the selected color to <code>color</code>.
     * Note that setting the color to <code>null</code>
     * is undefined and may have unpredictable results.
     * This method fires a state changed event if it sets the
     * current color to a new non-<code>null</code> color.
     *
     * @param color the new <code>Color</code>
     * @see   #getSelectedColor
     * @see   #addChangeListener
     */
    void setSelectedColor(Color color);

    /**
     * Adds <code>listener</code> as a listener to changes in the model.
     * @param listener the <code>ChangeListener</code> to be added
     */
    void addChangeListener(ChangeListener listener);

    /**
     * Removes <code>listener</code> as a listener to changes in the model.
     * @param listener the <code>ChangeListener</code> to be removed
     */
    void removeChangeListener(ChangeListener listener);
}

⏎ javax/swing/colorchooser/ColorSelectionModel.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - org.* Package Source Code

⇐ JRE 8 rt.jar - java.* Package Source Code

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