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/jaxp/validation/XMLSchema.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2005 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.jaxp.validation;

import com.sun.org.apache.xerces.internal.xni.grammars.XMLGrammarPool;

/**
 * <p>Implementation of Schema for W3C XML Schemas.</p>
 *
 * @author Michael Glavassevich, IBM
 */
final class XMLSchema extends AbstractXMLSchema {

    /** The grammar pool is immutable */
    private final XMLGrammarPool fGrammarPool;

    /** Constructor */
    public XMLSchema(XMLGrammarPool grammarPool) {
        fGrammarPool = grammarPool;
    }

    /*
     * XSGrammarPoolContainer methods
     */

    /**
     * <p>Returns the grammar pool contained inside the container.</p>
     *
     * @return the grammar pool contained inside the container
     */
    public XMLGrammarPool getGrammarPool() {
        return fGrammarPool;
    }

    /**
     * <p>Returns whether the schema components contained in this object
     * can be considered to be a fully composed schema and should be
     * used to exclusion of other schema components which may be
     * present elsewhere.</p>
     *
     * @return whether the schema components contained in this object
     * can be considered to be a fully composed schema
     */
    public boolean isFullyComposed() {
        return true;
    }

} // XMLSchema

⏎ com/sun/org/apache/xerces/internal/jaxp/validation/XMLSchema.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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