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/xalan/internal/xsltc/compiler/QName.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001-2004 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.
 */
/*
 * $Id: QName.java,v 1.2.4.1 2005/09/02 11:45:56 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler;

/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 * @author Morten Jorgensen
 */
final class QName {
    private final String _localname;
    private String _prefix;
    private String _namespace;
    private String _stringRep;
    private int    _hashCode;

    public QName(String namespace, String prefix, String localname) {
        _namespace = namespace;
        _prefix    = prefix;
        _localname = localname;

        _stringRep =
            (namespace != null && !namespace.equals(Constants.EMPTYSTRING)) ?
            (namespace + ':' + localname) : localname;

        _hashCode  = _stringRep.hashCode() + 19; // cached for speed
    }

    public void clearNamespace() {
        _namespace = Constants.EMPTYSTRING;
    }

    public String toString() {
        return _stringRep;
    }

    public String getStringRep() {
        return _stringRep;
    }

    public boolean equals(Object other) {
        return (this == other)
                   || (other instanceof QName
                           && _stringRep.equals(((QName) other).getStringRep()));
    }

    public String getLocalPart() {
        return _localname;
    }

    public String getNamespace() {
        return _namespace;
    }

    public String getPrefix() {
        return _prefix;
    }

    public int hashCode() {
        return _hashCode;
    }

    public String dump() {
        return "QName: " + _namespace + "(" + _prefix + "):" + _localname;
    }
}

⏎ com/sun/org/apache/xalan/internal/xsltc/compiler/QName.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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