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/MimeTypeParseException.java

/*
 * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.awt.datatransfer;


/**
 *    A class to encapsulate MimeType parsing related exceptions
 *
 * @serial exclude
 * @since 1.3
 */
public class MimeTypeParseException extends Exception {

    // use serialVersionUID from JDK 1.2.2 for interoperability
    private static final long serialVersionUID = -5604407764691570741L;

    /**
     * Constructs a MimeTypeParseException with no specified detail message.
     */
    public MimeTypeParseException() {
        super();
    }

    /**
     * Constructs a MimeTypeParseException with the specified detail message.
     *
     * @param   s   the detail message.
     */
    public MimeTypeParseException(String s) {
        super(s);
    }
} // class MimeTypeParseException

⏎ java/awt/datatransfer/MimeTypeParseException.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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