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/DropTargetEvent.java

/*
 * Copyright (c) 1997, 2008, 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.util.EventObject;
import java.awt.dnd.DropTargetContext;

/**
 * The <code>DropTargetEvent</code> is the base
 * class for both the <code>DropTargetDragEvent</code>
 * and the <code>DropTargetDropEvent</code>.
 * It encapsulates the current state of the Drag and
 * Drop operations, in particular the current
 * <code>DropTargetContext</code>.
 *
 * @since 1.2
 *
 */

public class DropTargetEvent extends java.util.EventObject {

    private static final long serialVersionUID = 2821229066521922993L;

    /**
     * Construct a <code>DropTargetEvent</code> object with
     * the specified <code>DropTargetContext</code>.
     * <P>
     * @param dtc The <code>DropTargetContext</code>
     * @throws NullPointerException if {@code dtc} equals {@code null}.
     * @see #getSource()
     * @see #getDropTargetContext()
     */

    public DropTargetEvent(DropTargetContext dtc) {
        super(dtc.getDropTarget());

        context  = dtc;
    }

    /**
     * This method returns the <code>DropTargetContext</code>
     * associated with this <code>DropTargetEvent</code>.
     * <P>
     * @return the <code>DropTargetContext</code>
     */

    public DropTargetContext getDropTargetContext() {
        return context;
    }

    /**
     * The <code>DropTargetContext</code> associated with this
     * <code>DropTargetEvent</code>.
     *
     * @serial
     */
    protected DropTargetContext   context;
}

⏎ java/awt/dnd/DropTargetEvent.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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