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/AnnotationDesc.java

/*
 * Copyright (c) 2003, 2013, 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;


/**
 * Represents an annotation.
 * An annotation associates a value with each element of an annotation type.
 *
 * @author Scott Seligman
 * @since 1.5
 */
public interface AnnotationDesc {

    /**
     * Returns the annotation type of this annotation.
     *
     * @return the annotation type of this annotation.
     */
    AnnotationTypeDoc annotationType();

    /**
     * Returns this annotation's elements and their values.
     * Only those explicitly present in the annotation are
     * included, not those assuming their default values.
     * Returns an empty array if there are none.
     *
     * @return this annotation's elements and their values.
     */
    ElementValuePair[] elementValues();

    /**
     * Check for the synthesized bit on the annotation.
     *
     * @return true if the annotation is synthesized.
     */
    boolean isSynthesized();

    /**
     * Represents an association between an annotation type element
     * and one of its values.
     *
     * @author Scott Seligman
     * @since 1.5
     */
    public interface ElementValuePair {

        /**
         * Returns the annotation type element.
         *
         * @return the annotation type element.
         */
        AnnotationTypeElementDoc element();

        /**
         * Returns the value associated with the annotation type element.
         *
         * @return the value associated with the annotation type element.
         */
        AnnotationValue value();
    }
}

⏎ com/sun/javadoc/AnnotationDesc.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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