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/URLStreamHandlerFactory.java

/*
 * Copyright (c) 1995, 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;

/**
 * This interface defines a factory for {@code URL} stream
 * protocol handlers.
 * <p>
 * It is used by the {@code URL} class to create a
 * {@code URLStreamHandler} for a specific protocol.
 *
 * @author  Arthur van Hoff
 * @see     java.net.URL
 * @see     java.net.URLStreamHandler
 * @since   JDK1.0
 */
public interface URLStreamHandlerFactory {
    /**
     * Creates a new {@code URLStreamHandler} instance with the specified
     * protocol.
     *
     * @param   protocol   the protocol ("{@code ftp}",
     *                     "{@code http}", "{@code nntp}", etc.).
     * @return  a {@code URLStreamHandler} for the specific protocol.
     * @see     java.net.URLStreamHandler
     */
    URLStreamHandler createURLStreamHandler(String protocol);
}

⏎ java/net/URLStreamHandlerFactory.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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