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/ContentHandlerFactory.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 content handlers. An
 * implementation of this interface should map a MIME type into an
 * instance of {@code ContentHandler}.
 * <p>
 * This interface is used by the {@code URLStreamHandler} class
 * to create a {@code ContentHandler} for a MIME type.
 *
 * @author  James Gosling
 * @see     java.net.ContentHandler
 * @see     java.net.URLStreamHandler
 * @since   JDK1.0
 */
public interface ContentHandlerFactory {
    /**
     * Creates a new {@code ContentHandler} to read an object from
     * a {@code URLStreamHandler}.
     *
     * @param   mimetype   the MIME type for which a content handler is desired.

     * @return  a new {@code ContentHandler} to read an object from a
     *          {@code URLStreamHandler}.
     * @see     java.net.ContentHandler
     * @see     java.net.URLStreamHandler
     */
    ContentHandler createContentHandler(String mimetype);
}

⏎ java/net/ContentHandlerFactory.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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