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/datatransfer/FlavorMap.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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 *
 *
 *
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 *
 */

package java.awt.datatransfer;

import java.util.Map;


/**
 * A two-way Map between "natives" (Strings), which correspond to platform-
 * specific data formats, and "flavors" (DataFlavors), which correspond to
 * platform-independent MIME types. FlavorMaps need not be symmetric, but
 * typically are.
 *
 *
 * @since 1.2
 */
public interface FlavorMap {

    /**
     * Returns a <code>Map</code> of the specified <code>DataFlavor</code>s to
     * their corresponding <code>String</code> native. The returned
     * <code>Map</code> is a modifiable copy of this <code>FlavorMap</code>'s
     * internal data. Client code is free to modify the <code>Map</code>
     * without affecting this object.
     *
     * @param flavors an array of <code>DataFlavor</code>s which will be the
     *        key set of the returned <code>Map</code>. If <code>null</code> is
     *        specified, a mapping of all <code>DataFlavor</code>s currently
     *        known to this <code>FlavorMap</code> to their corresponding
     *        <code>String</code> natives will be returned.
     * @return a <code>java.util.Map</code> of <code>DataFlavor</code>s to
     *         <code>String</code> natives
     */
    Map<DataFlavor,String> getNativesForFlavors(DataFlavor[] flavors);

    /**
     * Returns a <code>Map</code> of the specified <code>String</code> natives
     * to their corresponding <code>DataFlavor</code>. The returned
     * <code>Map</code> is a modifiable copy of this <code>FlavorMap</code>'s
     * internal data. Client code is free to modify the <code>Map</code>
     * without affecting this object.
     *
     * @param natives an array of <code>String</code>s which will be the
     *        key set of the returned <code>Map</code>. If <code>null</code> is
     *        specified, a mapping of all <code>String</code> natives currently
     *        known to this <code>FlavorMap</code> to their corresponding
     *        <code>DataFlavor</code>s will be returned.
     * @return a <code>java.util.Map</code> of <code>String</code> natives to
     *         <code>DataFlavor</code>s
     */
    Map<String,DataFlavor> getFlavorsForNatives(String[] natives);
}

⏎ java/awt/datatransfer/FlavorMap.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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