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/DnDConstants.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 java.awt.dnd;

import java.lang.annotation.Native;

/**
 * This class contains constant values representing
 * the type of action(s) to be performed by a Drag and Drop operation.
 * @since 1.2
 */
public final class DnDConstants {

    private DnDConstants() {} // define null private constructor.

    /**
     * An <code>int</code> representing no action.
     */
    @Native public static final int ACTION_NONE         = 0x0;

    /**
     * An <code>int</code> representing a &quot;copy&quot; action.
     */
    @Native public static final int ACTION_COPY         = 0x1;

    /**
     * An <code>int</code> representing a &quot;move&quot; action.
     */
    @Native public static final int ACTION_MOVE         = 0x2;

    /**
     * An <code>int</code> representing a &quot;copy&quot; or
     * &quot;move&quot; action.
     */
    @Native public static final int ACTION_COPY_OR_MOVE = ACTION_COPY | ACTION_MOVE;

    /**
     * An <code>int</code> representing a &quot;link&quot; action.
     *
     * The link verb is found in many, if not all native DnD platforms, and the
     * actual interpretation of LINK semantics is both platform
     * and application dependent. Broadly speaking, the
     * semantic is "do not copy, or move the operand, but create a reference
     * to it". Defining the meaning of "reference" is where ambiguity is
     * introduced.
     *
     * The verb is provided for completeness, but its use is not recommended
     * for DnD operations between logically distinct applications where
     * misinterpretation of the operations semantics could lead to confusing
     * results for the user.
     */

    @Native public static final int ACTION_LINK         = 0x40000000;

    /**
     * An <code>int</code> representing a &quot;reference&quot;
     * action (synonym for ACTION_LINK).
     */
    @Native public static final int ACTION_REFERENCE    = ACTION_LINK;

}

⏎ java/awt/dnd/DnDConstants.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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