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/PosixFileAttributes.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;

import java.util.Set;

/**
 * File attributes associated with files on file systems used by operating systems
 * that implement the Portable Operating System Interface (POSIX) family of
 * standards.
 *
 * <p> The POSIX attributes of a file are retrieved using a {@link
 * PosixFileAttributeView} by invoking its {@link
 * PosixFileAttributeView#readAttributes readAttributes} method.
 *
 * @since 1.7
 */

public interface PosixFileAttributes
    extends BasicFileAttributes
{
    /**
     * Returns the owner of the file.
     *
     * @return  the file owner
     *
     * @see PosixFileAttributeView#setOwner
     */
    UserPrincipal owner();

    /**
     * Returns the group owner of the file.
     *
     * @return  the file group owner
     *
     * @see PosixFileAttributeView#setGroup
     */
    GroupPrincipal group();

    /**
     * Returns the permissions of the file. The file permissions are returned
     * as a set of {@link PosixFilePermission} elements. The returned set is a
     * copy of the file permissions and is modifiable. This allows the result
     * to be modified and passed to the {@link PosixFileAttributeView#setPermissions
     * setPermissions} method to update the file's permissions.
     *
     * @return  the file permissions
     *
     * @see PosixFileAttributeView#setPermissions
     */
    Set<PosixFilePermission> permissions();
}

⏎ java/nio/file/attribute/PosixFileAttributes.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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