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/dom/DOMStringListImpl.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.dom;

import java.util.Vector;

import org.w3c.dom.DOMStringList;

/**
 * DOM Level 3
 *
 * This class implements the DOM Level 3 Core interface DOMStringList.
 *
 * @xerces.internal
 *
 * @author Neil Delima, IBM
 */
public class DOMStringListImpl implements DOMStringList {

        //A collection of DOMString values
    private Vector fStrings;

    /**
     * Construct an empty list of DOMStringListImpl
     */
    public DOMStringListImpl() {
        fStrings = new Vector();
    }

    /**
     * Construct an empty list of DOMStringListImpl
     */
    public DOMStringListImpl(Vector params) {
        fStrings = params;
    }

        /**
         * @see org.w3c.dom.DOMStringList#item(int)
         */
        public String item(int index) {
        try {
            return (String) fStrings.elementAt(index);
        } catch (ArrayIndexOutOfBoundsException e) {
            return null;
        }
        }

        /**
         * @see org.w3c.dom.DOMStringList#getLength()
         */
        public int getLength() {
                return fStrings.size();
        }

        /**
         * @see org.w3c.dom.DOMStringList#contains(String)
         */
        public boolean contains(String param) {
                return fStrings.contains(param) ;
        }

    /**
     * DOM Internal:
     * Add a <code>DOMString</code> to the list.
     *
     * @param domString A string to add to the list
     */
    public void add(String param) {
        fStrings.add(param);
    }

}

⏎ com/sun/org/apache/xerces/internal/dom/DOMStringListImpl.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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