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/io/InvalidClassException.java

/*
 * Copyright (c) 1996, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.io;

/**
 * Thrown when the Serialization runtime detects one of the following
 * problems with a Class.
 * <UL>
 * <LI> The serial version of the class does not match that of the class
 *      descriptor read from the stream
 * <LI> The class contains unknown datatypes
 * <LI> The class does not have an accessible no-arg constructor
 * </UL>
 *
 * @author  unascribed
 * @since   JDK1.1
 */
public class InvalidClassException extends ObjectStreamException {

    private static final long serialVersionUID = -4333316296251054416L;

    /**
     * Name of the invalid class.
     *
     * @serial Name of the invalid class.
     */
    public String classname;

    /**
     * Report an InvalidClassException for the reason specified.
     *
     * @param reason  String describing the reason for the exception.
     */
    public InvalidClassException(String reason) {
        super(reason);
    }

    /**
     * Constructs an InvalidClassException object.
     *
     * @param cname   a String naming the invalid class.
     * @param reason  a String describing the reason for the exception.
     */
    public InvalidClassException(String cname, String reason) {
        super(reason);
        classname = cname;
    }

    /**
     * Produce the message and include the classname, if present.
     */
    public String getMessage() {
        if (classname == null)
            return super.getMessage();
        else
            return classname + "; " + super.getMessage();
    }
}

⏎ java/io/InvalidClassException.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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