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/AnnotationTypeMismatchException.java

/*
 * Copyright (c) 2003, 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;
import java.lang.reflect.Method;

/**
 * Thrown to indicate that a program has attempted to access an element of
 * an annotation whose type has changed after the annotation was compiled
 * (or serialized).
 * 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 AnnotationTypeMismatchException extends RuntimeException {
    private static final long serialVersionUID = 8125925355765570191L;

    /**
     * The <tt>Method</tt> object for the annotation element.
     */
    private final Method element;

    /**
     * The (erroneous) type of data found in the annotation.  This string
     * may, but is not required to, contain the value as well.  The exact
     * format of the string is unspecified.
     */
    private final String foundType;

    /**
     * Constructs an AnnotationTypeMismatchException for the specified
     * annotation type element and found data type.
     *
     * @param element the <tt>Method</tt> object for the annotation element
     * @param foundType the (erroneous) type of data found in the annotation.
     *        This string may, but is not required to, contain the value
     *        as well.  The exact format of the string is unspecified.
     */
    public AnnotationTypeMismatchException(Method element, String foundType) {
        super("Incorrectly typed data found for annotation element " + element
              + " (Found data of type " + foundType + ")");
        this.element = element;
        this.foundType = foundType;
    }

    /**
     * Returns the <tt>Method</tt> object for the incorrectly typed element.
     *
     * @return the <tt>Method</tt> object for the incorrectly typed element
     */
    public Method element() {
        return this.element;
    }

    /**
     * Returns the type of data found in the incorrectly typed element.
     * The returned string may, but is not required to, contain the value
     * as well.  The exact format of the string is unspecified.
     *
     * @return the type of data found in the incorrectly typed element
     */
    public String foundType() {
        return this.foundType;
    }
}

⏎ java/lang/annotation/AnnotationTypeMismatchException.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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