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/dnd/Autoscroll.java

/*
 * Copyright (c) 1998, 1999, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package java.awt.dnd;

import java.awt.Insets;
import java.awt.Point;

/**
 * During DnD operations it is possible that a user may wish to drop the
 * subject of the operation on a region of a scrollable GUI control that is
 * not currently visible to the user.
 * <p>
 * In such situations it is desirable that the GUI control detect this
 * and institute a scroll operation in order to make obscured region(s)
 * visible to the user. This feature is known as autoscrolling.
 * <p>
 * If a GUI control is both an active <code>DropTarget</code>
 * and is also scrollable, it
 * can receive notifications of autoscrolling gestures by the user from
 * the DnD system by implementing this interface.
 * <p>
 * An autoscrolling gesture is initiated by the user by keeping the drag
 * cursor motionless with a border region of the <code>Component</code>,
 * referred to as
 * the "autoscrolling region", for a predefined period of time, this will
 * result in repeated scroll requests to the <code>Component</code>
 * until the drag <code>Cursor</code> resumes its motion.
 *
 * @since 1.2
 */

public interface Autoscroll {

    /**
     * This method returns the <code>Insets</code> describing
     * the autoscrolling region or border relative
     * to the geometry of the implementing Component.
     * <P>
     * This value is read once by the <code>DropTarget</code>
     * upon entry of the drag <code>Cursor</code>
     * into the associated <code>Component</code>.
     * <P>
     * @return the Insets
     */

    public Insets getAutoscrollInsets();

    /**
     * notify the <code>Component</code> to autoscroll
     * <P>
     * @param cursorLocn A <code>Point</code> indicating the
     * location of the cursor that triggered this operation.
     */

    public void autoscroll(Point cursorLocn);

}

⏎ java/awt/dnd/Autoscroll.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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