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/IncompleteAnnotationException.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 java.lang.annotation;

/**
 * Thrown to indicate that a program has attempted to access an element of
 * an annotation type that was added to the annotation type definition after
 * the annotation was compiled (or serialized).  This exception will not be
 * thrown if the new element has a default value.
 * This exception 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 IncompleteAnnotationException extends RuntimeException {
    private static final long serialVersionUID = 8445097402741811912L;

    private Class<? extends Annotation> annotationType;
    private String elementName;

    /**
     * Constructs an IncompleteAnnotationException to indicate that
     * the named element was missing from the specified annotation type.
     *
     * @param annotationType the Class object for the annotation type
     * @param elementName the name of the missing element
     * @throws NullPointerException if either parameter is {@code null}
     */
    public IncompleteAnnotationException(
            Class<? extends Annotation> annotationType,
            String elementName) {
        super(annotationType.getName() + " missing element " +
              elementName.toString());

        this.annotationType = annotationType;
        this.elementName = elementName;
    }

    /**
     * Returns the Class object for the annotation type with the
     * missing element.
     *
     * @return the Class object for the annotation type with the
     *     missing element
     */
    public Class<? extends Annotation> annotationType() {
        return annotationType;
    }

    /**
     * Returns the name of the missing element.
     *
     * @return the name of the missing element
     */
    public String elementName() {
        return elementName;
    }
}

⏎ java/lang/annotation/IncompleteAnnotationException.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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