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/net/CookieStore.java

/*
 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.net;

import java.util.List;
import java.util.Map;

/**
 * A CookieStore object represents a storage for cookie. Can store and retrieve
 * cookies.
 *
 * <p>{@link CookieManager} will call {@code CookieStore.add} to save cookies
 * for every incoming HTTP response, and call {@code CookieStore.get} to
 * retrieve cookie for every outgoing HTTP request. A CookieStore
 * is responsible for removing HttpCookie instances which have expired.
 *
 * @author Edward Wang
 * @since 1.6
 */
public interface CookieStore {
    /**
     * Adds one HTTP cookie to the store. This is called for every
     * incoming HTTP response.
     *
     * <p>A cookie to store may or may not be associated with an URI. If it
     * is not associated with an URI, the cookie's domain and path attribute
     * will indicate where it comes from. If it is associated with an URI and
     * its domain and path attribute are not specified, given URI will indicate
     * where this cookie comes from.
     *
     * <p>If a cookie corresponding to the given URI already exists,
     * then it is replaced with the new one.
     *
     * @param uri       the uri this cookie associated with.
     *                  if {@code null}, this cookie will not be associated
     *                  with an URI
     * @param cookie    the cookie to store
     *
     * @throws NullPointerException if {@code cookie} is {@code null}
     *
     * @see #get
     *
     */
    public void add(URI uri, HttpCookie cookie);


    /**
     * Retrieve cookies associated with given URI, or whose domain matches the
     * given URI. Only cookies that have not expired are returned.
     * This is called for every outgoing HTTP request.
     *
     * @return          an immutable list of HttpCookie,
     *                  return empty list if no cookies match the given URI
     *
     * @param uri       the uri associated with the cookies to be returned
     *
     * @throws NullPointerException if {@code uri} is {@code null}
     *
     * @see #add
     *
     */
    public List<HttpCookie> get(URI uri);


    /**
     * Get all not-expired cookies in cookie store.
     *
     * @return          an immutable list of http cookies;
     *                  return empty list if there's no http cookie in store
     */
    public List<HttpCookie> getCookies();


    /**
     * Get all URIs which identify the cookies in this cookie store.
     *
     * @return          an immutable list of URIs;
     *                  return empty list if no cookie in this cookie store
     *                  is associated with an URI
     */
    public List<URI> getURIs();


    /**
     * Remove a cookie from store.
     *
     * @param uri       the uri this cookie associated with.
     *                  if {@code null}, the cookie to be removed is not associated
     *                  with an URI when added; if not {@code null}, the cookie
     *                  to be removed is associated with the given URI when added.
     * @param cookie    the cookie to remove
     *
     * @return          {@code true} if this store contained the specified cookie
     *
     * @throws NullPointerException if {@code cookie} is {@code null}
     */
    public boolean remove(URI uri, HttpCookie cookie);


    /**
     * Remove all cookies in this cookie store.
     *
     * @return          {@code true} if this store changed as a result of the call
     */
    public boolean removeAll();
}

⏎ java/net/CookieStore.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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