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/FileVisitResult.java

/*
 * Copyright (c) 2007, 2009, 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;

/**
 * The result type of a {@link FileVisitor FileVisitor}.
 *
 * @since 1.7
 *
 * @see Files#walkFileTree
 */

public enum FileVisitResult {
    /**
     * Continue. When returned from a {@link FileVisitor#preVisitDirectory
     * preVisitDirectory} method then the entries in the directory should also
     * be visited.
     */
    CONTINUE,
    /**
     * Terminate.
     */
    TERMINATE,
    /**
     * Continue without visiting the entries in this directory. This result
     * is only meaningful when returned from the {@link
     * FileVisitor#preVisitDirectory preVisitDirectory} method; otherwise
     * this result type is the same as returning {@link #CONTINUE}.
     */
    SKIP_SUBTREE,
    /**
     * Continue without visiting the <em>siblings</em> of this file or directory.
     * If returned from the {@link FileVisitor#preVisitDirectory
     * preVisitDirectory} method then the entries in the directory are also
     * skipped and the {@link FileVisitor#postVisitDirectory postVisitDirectory}
     * method is not invoked.
     */
    SKIP_SIBLINGS;
}

⏎ java/nio/file/FileVisitResult.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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