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/xs/YearMonthDurationDV.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2004,2005 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.impl.dv.xs;

import java.math.BigInteger;

import javax.xml.datatype.DatatypeConstants;
import javax.xml.datatype.Duration;

import com.sun.org.apache.xerces.internal.impl.dv.InvalidDatatypeValueException;
import com.sun.org.apache.xerces.internal.impl.dv.ValidationContext;

/**
 * Used to validate the <yearMonthDuration> type
 *
 * @xerces.internal
 *
 * @author Ankit Pasricha, IBM
 *
 * @version $Id: YearMonthDurationDV.java,v 1.6 2010-11-01 04:39:47 joehw Exp $
 */
class YearMonthDurationDV extends DurationDV {

    public Object getActualValue(String content, ValidationContext context)
        throws InvalidDatatypeValueException {
        try {
            return parse(content, DurationDV.YEARMONTHDURATION_TYPE);
        }
        catch (Exception ex) {
            throw new InvalidDatatypeValueException("cvc-datatype-valid.1.2.1", new Object[]{content, "yearMonthDuration"});
        }
    }

    protected Duration getDuration(DateTimeData date) {
        int sign = 1;
        if ( date.year<0 || date.month<0) {
            sign = -1;
        }
        return datatypeFactory.newDuration(sign == 1,
                date.year != DatatypeConstants.FIELD_UNDEFINED?BigInteger.valueOf(sign*date.year):null,
                date.month != DatatypeConstants.FIELD_UNDEFINED?BigInteger.valueOf(sign*date.month):null,
                null,
                null,
                null,
                null);
    }
}

⏎ com/sun/org/apache/xerces/internal/impl/dv/xs/YearMonthDurationDV.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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