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/NamedNodeMapImpl.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001, 2002,2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

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

import org.w3c.dom.Node;
import org.w3c.dom.Attr;
import org.w3c.dom.NamedNodeMap;

import org.w3c.dom.DOMException;


/**
 * @xerces.internal
 *
 * @author Rahul Srivastava, Sun Microsystems Inc.
 *
 */
public class NamedNodeMapImpl implements NamedNodeMap {

        Attr[] attrs;

        public NamedNodeMapImpl(Attr[] attrs) {
                this.attrs = attrs;
        }

        public Node getNamedItem(String name) {
                for (int i=0; i<attrs.length; i++) {
                        if (attrs[i].getName().equals(name)) {
                                return attrs[i];
                        }
                }
                return null;
        }

        public Node item(int index) {
                if (index < 0 && index > getLength()) {
                        return null;
                }
                return attrs[index];
        }

        public int getLength() {
                return attrs.length;
        }

        public Node getNamedItemNS(String namespaceURI, String localName) {
                for (int i=0; i<attrs.length; i++) {
                        if (attrs[i].getName().equals(localName) && attrs[i].getNamespaceURI().equals(namespaceURI)) {
                                return attrs[i];
                        }
                }
                return null;
        }

        public Node setNamedItemNS(Node arg) throws DOMException {
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported");
        }

        public Node setNamedItem(Node arg) throws DOMException {
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported");
        }

        public Node removeNamedItem(String name) throws DOMException {
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported");
        }

        public Node removeNamedItemNS(String namespaceURI, String localName) throws DOMException {
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported");
        }
}

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