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/dv/dtd/XML11DTDDVFactoryImpl.java

/*
 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
 */
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.dv.dtd;

import com.sun.org.apache.xerces.internal.impl.dv.DatatypeValidator;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

/**
 * the factory to create/return built-in XML 1.1 DVs and create user-defined DVs
 *
 * @xerces.internal
 *
 * @author Neil Graham, IBM
 *
 */
public class XML11DTDDVFactoryImpl extends DTDDVFactoryImpl {

    static Map<String, DatatypeValidator> XML11BUILTINTYPES;
    static {
        Map<String, DatatypeValidator> xml11BuiltInTypes = new HashMap<>();
        xml11BuiltInTypes.put("XML11ID", new XML11IDDatatypeValidator());
        DatatypeValidator dvTemp = new XML11IDREFDatatypeValidator();
        xml11BuiltInTypes.put("XML11IDREF", dvTemp);
        xml11BuiltInTypes.put("XML11IDREFS", new ListDatatypeValidator(dvTemp));
        dvTemp = new XML11NMTOKENDatatypeValidator();
        xml11BuiltInTypes.put("XML11NMTOKEN", dvTemp);
        xml11BuiltInTypes.put("XML11NMTOKENS", new ListDatatypeValidator(dvTemp));
        XML11BUILTINTYPES = Collections.unmodifiableMap(xml11BuiltInTypes);
    } // <clinit>

    /**
     * return a dtd type of the given name
     * This will call the super class if and only if it does not
     * recognize the passed-in name.
     *
     * @param name  the name of the datatype
     * @return      the datatype validator of the given name
     */
    @Override
    public DatatypeValidator getBuiltInDV(String name) {
        if(XML11BUILTINTYPES.get(name) != null) {
            return XML11BUILTINTYPES.get(name);
        }
        return fBuiltInTypes.get(name);
    }

    /**
     * get all built-in DVs, which are stored in a Map keyed by the name
     * New XML 1.1 datatypes are inserted.
     *
     * @return      a Map which contains all datatypes
     */
    @Override
    public Map<String, DatatypeValidator> getBuiltInTypes() {
        final HashMap<String, DatatypeValidator> toReturn = new HashMap<>(fBuiltInTypes);
        toReturn.putAll(XML11BUILTINTYPES);
        return toReturn;
    }
}//XML11DTDDVFactoryImpl

⏎ com/sun/org/apache/xerces/internal/impl/dv/dtd/XML11DTDDVFactoryImpl.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
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