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/event/TableColumnModelEvent.java

/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package javax.swing.event;

import java.util.EventObject;
import javax.swing.table.*;

/**
 * <B>TableColumnModelEvent</B> is used to notify listeners that a table
 * column model has changed, such as a column was added, removed, or
 * moved.
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author Alan Chung
 * @see TableColumnModelListener
 */
public class TableColumnModelEvent extends java.util.EventObject
{
//
//  Instance Variables
//

    /** The index of the column from where it was moved or removed */
    protected int       fromIndex;

    /** The index of the column to where it was moved or added */
    protected int       toIndex;

//
// Constructors
//

    /**
     * Constructs a {@code TableColumnModelEvent} object.
     *
     * @param source  the {@code TableColumnModel} that originated the event
     * @param from    an int specifying the index from where the column was
     *                moved or removed
     * @param to      an int specifying the index to where the column was
     *                moved or added
     * @see #getFromIndex
     * @see #getToIndex
     */
    public TableColumnModelEvent(TableColumnModel source, int from, int to) {
        super(source);
        fromIndex = from;
        toIndex = to;
    }

//
// Querying Methods
//

    /** Returns the fromIndex.  Valid for removed or moved events */
    public int getFromIndex() { return fromIndex; };

    /** Returns the toIndex.  Valid for add and moved events */
    public int getToIndex() { return toIndex; };
}

⏎ javax/swing/event/TableColumnModelEvent.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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