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/nio/file/attribute/DosFileAttributes.java

/*
 * Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.nio.file.attribute;

/**
 * File attributes associated with a file in a file system that supports
 * legacy "DOS" attributes.
 *
 * <p> <b>Usage Example:</b>
 * <pre>
 *    Path file = ...
 *    DosFileAttributes attrs = Files.readAttributes(file, DosFileAttributes.class);
 * </pre>
 *
 * @since 1.7
 */

public interface DosFileAttributes
    extends BasicFileAttributes
{
    /**
     * Returns the value of the read-only attribute.
     *
     * <p> This attribute is often used as a simple access control mechanism
     * to prevent files from being deleted or updated. Whether the file system
     * or platform does any enforcement to prevent <em>read-only</em> files
     * from being updated is implementation specific.
     *
     * @return  the value of the read-only attribute
     */
    boolean isReadOnly();

    /**
     * Returns the value of the hidden attribute.
     *
     * <p> This attribute is often used to indicate if the file is visible to
     * users.
     *
     * @return  the value of the hidden attribute
     */
    boolean isHidden();

    /**
     * Returns the value of the archive attribute.
     *
     * <p> This attribute is typically used by backup programs.
     *
     * @return  the value of the archive attribute
     */
    boolean isArchive();

    /**
     * Returns the value of the system attribute.
     *
     * <p> This attribute is often used to indicate that the file is a component
     * of the operating system.
     *
     * @return  the value of the system attribute
     */
    boolean isSystem();
}

⏎ java/nio/file/attribute/DosFileAttributes.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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