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/XML11IDDatatypeValidator.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2002,2004 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.dv.dtd;

import com.sun.org.apache.xerces.internal.impl.dv.*;
import com.sun.org.apache.xerces.internal.util.XML11Char;

/**
 * <P>IDDatatypeValidator - ID represents the ID attribute
 * type from XML 1.1 Recommendation. The value space
 * of ID is the set of all strings that match the
 * NCName production and have been used in an XML
 * document. The lexical space of ID is the set of all
 * strings that match the NCName production.</P>
 * <P>The value space of ID is scoped to a specific
 * instance document.</P>
 * <P>The following constraint applies:
 * An ID must not appear more than once in an XML
 * document as a value of this type; i.e., ID values
 * must uniquely identify the elements which bear
 * them.</P>
 *
 * @xerces.internal
 *
 * @author Jeffrey Rodriguez, IBM
 * @author Sandy Gao, IBM
 * @author Neil Graham, IBM
 *
 */
public class XML11IDDatatypeValidator extends IDDatatypeValidator {

    // construct an ID datatype validator
    public XML11IDDatatypeValidator() {
        super();
    }

    /**
     * Checks that "content" string is valid ID value.
     * If invalid a Datatype validation exception is thrown.
     *
     * @param content       the string value that needs to be validated
     * @param context       the validation context
     * @throws InvalidDatatypeException if the content is
     *         invalid according to the rules for the validators
     * @see InvalidDatatypeValueException
     */
    public void validate(String content, ValidationContext context) throws InvalidDatatypeValueException {

        //Check if is valid key-[81] EncName ::= [A-Za-z] ([A-Za-z0-9._] | '-')*
        if(context.useNamespaces()) {
            if (!XML11Char.isXML11ValidNCName(content)) {
                throw new InvalidDatatypeValueException("IDInvalidWithNamespaces", new Object[]{content});
            }
        }
        else {
            if (!XML11Char.isXML11ValidName(content)) {
                throw new InvalidDatatypeValueException("IDInvalid", new Object[]{content});
            }
        }

        if (context.isIdDeclared(content)) {
            throw new InvalidDatatypeValueException("IDNotUnique", new Object[]{content});
        }

        context.addId(content);
    }

}

⏎ com/sun/org/apache/xerces/internal/impl/dv/dtd/XML11IDDatatypeValidator.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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