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 com.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ com/sun/javadoc/Parameter.java

/*
 * Copyright (c) 1998, 2004, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package com.sun.javadoc;

/**
 * Parameter information.
 * This includes a parameter type and parameter name.
 *
 * @author Robert Field
 */
public interface Parameter {

    /**
     * Get the type of this parameter.
     */
    Type type();

    /**
     * Get local name of this parameter.
     * For example if parameter is the short 'index', returns "index".
     */
    String name();

    /**
     * Get type name of this parameter.
     * For example if parameter is the short 'index', returns "short".
     * <p>
     * This method returns a complete string
     * representation of the type, including the dimensions of arrays and
     * the type arguments of parameterized types.  Names are qualified.
     */
    String typeName();

    /**
     * Returns a string representation of the parameter.
     * <p>
     * For example if parameter is the short 'index', returns "short index".
     *
     * @return type and parameter name of this parameter.
     */
    String toString();

    /**
     * Get the annotations of this parameter.
     * Return an empty array if there are none.
     *
     * @return the annotations of this parameter.
     * @since 1.5
     */
    AnnotationDesc[] annotations();
}

⏎ com/sun/javadoc/Parameter.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
Download 

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