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 com.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ com/sun/org/apache/xerces/internal/impl/xs/opti/AttrImpl.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 2001, 2002 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Xerces" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation and was
 * originally based on software copyright (c) 2001, International
 * Business Machines, Inc., http://www.apache.org.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package com.sun.org.apache.xerces.internal.impl.xs.opti;

import org.w3c.dom.Attr;
import org.w3c.dom.DOMException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.TypeInfo;

/**
 * This class represents a single attribute.
 *
 * @author Rahul Srivastava, Sun Microsystems Inc.
 *
 * @version $Id: AttrImpl.java,v 1.5 2010-11-01 04:40:01 joehw Exp $
 */
public class AttrImpl extends NodeImpl
                      implements Attr {

    Element element;
    String value;

    /** Default Constructor */
    public AttrImpl() {
        nodeType = Node.ATTRIBUTE_NODE;
    }

    /**
     * Constructs an attribute.
     *
     * @param element Element which owns this attribute
     * @param prefix The QName prefix.
     * @param localpart The QName localpart.
     * @param rawname The QName rawname.
     * @param uri The uri binding for the associated prefix.
     * @param value The value of the attribute.
     */
    public AttrImpl(Element element, String prefix, String localpart, String rawname, String uri, String value) {
        super(prefix, localpart, rawname, uri, Node.ATTRIBUTE_NODE);
        this.element = element;
        this.value = value;
    }

    public String getName() {
        return rawname;
    }

    public boolean getSpecified() {
        return true;
    }

    public String getValue() {
        return value;
    }

    public String getNodeValue() {
        return getValue();
    }

    public Element getOwnerElement() {
        return element;
    }

    public Document getOwnerDocument() {
        return element.getOwnerDocument();
    }

    public void setValue(String value) throws DOMException {
        this.value = value;
    }

    /**
     * @since DOM Level 3
     */
    public boolean isId(){
        return false;
    }

    /**
     * Method getSchemaTypeInfo.
     * @return TypeInfo
     */
    public TypeInfo getSchemaTypeInfo(){
      return null;
    }

    /** NON-DOM method for debugging convenience */
    public String toString() {
        return getName() + "=" + "\"" + getValue() + "\"";
    }
}

⏎ com/sun/org/apache/xerces/internal/impl/xs/opti/AttrImpl.java

Or download all of them as a single archive file:

File name: jre-rt-com-1.8.0_191-src.zip
File size: 8099783 bytes
Release date: 2018-10-28
Download 

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