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/ExternalSubsetResolver.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 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;

import java.io.IOException;

import com.sun.org.apache.xerces.internal.xni.XNIException;
import com.sun.org.apache.xerces.internal.xni.grammars.XMLDTDDescription;
import com.sun.org.apache.xerces.internal.xni.parser.XMLEntityResolver;
import com.sun.org.apache.xerces.internal.xni.parser.XMLInputSource;

/**
 * <p>This interface extends <code>XMLEntityResolver</code> providing
 * a method to resolve external subsets for documents which do not
 * explicitly provide one. The application can register an object that
 * implements this interface with the parser configuration. If registered,
 * it will be queried to locate an external subset when none is provided,
 * even for documents that do not contain DOCTYPE declarations. If the
 * registered external subset resolver does not provide an external subset
 * for a given document, it should return <code>null</code>.</p>
 *
 * @xerces.internal
 *
 * @author Michael Glavassevich, IBM
 *
 */
public interface ExternalSubsetResolver
    extends XMLEntityResolver {

    //
    // ExternalSubsetResolver methods
    //

    /**
     * <p>Locates an external subset for documents which do not explicitly
     * provide one. If no external subset is provided, this method should
     * return <code>null</code>.</p>
     *
     * @param grammarDescription a description of the DTD
     *
     * @throws XNIException Thrown on general error.
     * @throws IOException  Thrown if resolved entity stream cannot be
     *                      opened or some other i/o error occurs.
     */
    public XMLInputSource getExternalSubset(XMLDTDDescription grammarDescription)
        throws XNIException, IOException;

} // interface ExternalSubsetResolver

⏎ com/sun/org/apache/xerces/internal/impl/ExternalSubsetResolver.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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