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/lang/annotation/AnnotationFormatError.java

/*
 * Copyright (c) 2004, 2008, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package java.lang.annotation;

/**
 * Thrown when the annotation parser attempts to read an annotation
 * from a class file and determines that the annotation is malformed.
 * This error can be thrown by the {@linkplain
 * java.lang.reflect.AnnotatedElement API used to read annotations
 * reflectively}.
 *
 * @author  Josh Bloch
 * @see     java.lang.reflect.AnnotatedElement
 * @since   1.5
 */
public class AnnotationFormatError extends Error {
    private static final long serialVersionUID = -4256701562333669892L;

    /**
     * Constructs a new <tt>AnnotationFormatError</tt> with the specified
     * detail message.
     *
     * @param   message   the detail message.
     */
    public AnnotationFormatError(String message) {
        super(message);
    }

    /**
     * Constructs a new <tt>AnnotationFormatError</tt> with the specified
     * detail message and cause.  Note that the detail message associated
     * with <code>cause</code> is <i>not</i> automatically incorporated in
     * this error's detail message.
     *
     * @param  message the detail message
     * @param  cause the cause (A <tt>null</tt> value is permitted, and
     *     indicates that the cause is nonexistent or unknown.)
     */
    public AnnotationFormatError(String message, Throwable cause) {
        super(message, cause);
    }


    /**
     * Constructs a new <tt>AnnotationFormatError</tt> with the specified
     * cause and a detail message of
     * <tt>(cause == null ? null : cause.toString())</tt> (which
     * typically contains the class and detail message of <tt>cause</tt>).
     *
     * @param  cause the cause (A <tt>null</tt> value is permitted, and
     *     indicates that the cause is nonexistent or unknown.)
     */
    public AnnotationFormatError(Throwable cause) {
        super(cause);
    }
}

⏎ java/lang/annotation/AnnotationFormatError.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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