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/beans/SimpleBeanInfo.java

/*
 * Copyright (c) 1996, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package java.beans;

import java.awt.Image;
import java.awt.Toolkit;
import java.awt.image.ImageProducer;
import java.net.URL;

/**
 * This is a support class to make it easier for people to provide
 * BeanInfo classes.
 * <p>
 * It defaults to providing "noop" information, and can be selectively
 * overriden to provide more explicit information on chosen topics.
 * When the introspector sees the "noop" values, it will apply low
 * level introspection and design patterns to automatically analyze
 * the target bean.
 */

public class SimpleBeanInfo implements BeanInfo {

    /**
     * Deny knowledge about the class and customizer of the bean.
     * You can override this if you wish to provide explicit info.
     */
    public BeanDescriptor getBeanDescriptor() {
        return null;
    }

    /**
     * Deny knowledge of properties. You can override this
     * if you wish to provide explicit property info.
     */
    public PropertyDescriptor[] getPropertyDescriptors() {
        return null;
    }

    /**
     * Deny knowledge of a default property. You can override this
     * if you wish to define a default property for the bean.
     */
    public int getDefaultPropertyIndex() {
        return -1;
    }

    /**
     * Deny knowledge of event sets. You can override this
     * if you wish to provide explicit event set info.
     */
    public EventSetDescriptor[] getEventSetDescriptors() {
        return null;
    }

    /**
     * Deny knowledge of a default event. You can override this
     * if you wish to define a default event for the bean.
     */
    public int getDefaultEventIndex() {
        return -1;
    }

    /**
     * Deny knowledge of methods. You can override this
     * if you wish to provide explicit method info.
     */
    public MethodDescriptor[] getMethodDescriptors() {
        return null;
    }

    /**
     * Claim there are no other relevant BeanInfo objects.  You
     * may override this if you want to (for example) return a
     * BeanInfo for a base class.
     */
    public BeanInfo[] getAdditionalBeanInfo() {
        return null;
    }

    /**
     * Claim there are no icons available.  You can override
     * this if you want to provide icons for your bean.
     */
    public Image getIcon(int iconKind) {
        return null;
    }

    /**
     * This is a utility method to help in loading icon images.
     * It takes the name of a resource file associated with the
     * current object's class file and loads an image object
     * from that file.  Typically images will be GIFs.
     * <p>
     * @param resourceName  A pathname relative to the directory
     *          holding the class file of the current class.  For example,
     *          "wombat.gif".
     * @return  an image object.  May be null if the load failed.
     */
    public Image loadImage(final String resourceName) {
        try {
            final URL url = getClass().getResource(resourceName);
            if (url != null) {
                final ImageProducer ip = (ImageProducer) url.getContent();
                if (ip != null) {
                    return Toolkit.getDefaultToolkit().createImage(ip);
                }
            }
        } catch (final Exception ignored) {
        }
        return null;
    }
}

⏎ java/beans/SimpleBeanInfo.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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