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/dom/DOMLocatorImpl.java

/*
 * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001, 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.dom;

import org.w3c.dom.DOMLocator;
import org.w3c.dom.Node;


/**
 * <code>DOMLocatorImpl</code> is an implementaion that describes a location (e.g.
 * where an error occured).
 * <p>See also the <a href='http://www.w3.org/TR/2001/WD-DOM-Level-3-Core-20010913'>Document Object Model (DOM) Level 3 Core Specification</a>.
 *
 * @xerces.internal
 *
 * @author Gopal Sharma, SUN Microsystems Inc.
 */

public class DOMLocatorImpl implements DOMLocator {

    //
    // Data
    //

   /**
    * The column number where the error occured,
    * or -1 if there is no column number available.
    */
   public int fColumnNumber = -1;

   /**
    * The line number where the error occured,
    * or -1 if there is no line number available.
    */
   public int fLineNumber = -1;

   /** related data node*/
   public Node fRelatedNode = null;

   /**
    * The URI where the error occured,
    * or null if there is no URI available.
    */
   public String fUri = null;

   /**
    * The byte offset into the input source this locator is pointing to or -1
    * if there is no byte offset available
    */
   public int fByteOffset = -1;

   /**
    * The UTF-16, as defined in [Unicode] and Amendment 1 of [ISO/IEC 10646],
    * offset into the input source this locator is pointing to or -1 if there
    * is no UTF-16 offset available.
    */
   public int fUtf16Offset = -1;

   //
   // Constructors
   //

   public DOMLocatorImpl(){
   }

   public DOMLocatorImpl (int lineNumber, int columnNumber, String uri ){
        fLineNumber = lineNumber ;
        fColumnNumber = columnNumber ;
        fUri = uri;
   } // DOMLocatorImpl (int lineNumber, int columnNumber, String uri )

   public DOMLocatorImpl (int lineNumber, int columnNumber, int utf16Offset, String uri ){
        fLineNumber = lineNumber ;
        fColumnNumber = columnNumber ;
        fUri = uri;
        fUtf16Offset = utf16Offset;
   } // DOMLocatorImpl (int lineNumber, int columnNumber, int utf16Offset, String uri )

   public DOMLocatorImpl (int lineNumber, int columnNumber, int byteoffset, Node relatedData, String uri ){
        fLineNumber = lineNumber ;
        fColumnNumber = columnNumber ;
        fByteOffset = byteoffset ;
        fRelatedNode = relatedData ;
        fUri = uri;
   } // DOMLocatorImpl (int lineNumber, int columnNumber, int offset, Node errorNode, String uri )

   public DOMLocatorImpl (int lineNumber, int columnNumber, int byteoffset, Node relatedData, String uri, int utf16Offset ){
        fLineNumber = lineNumber ;
        fColumnNumber = columnNumber ;
        fByteOffset = byteoffset ;
        fRelatedNode = relatedData ;
        fUri = uri;
        fUtf16Offset = utf16Offset;
   } // DOMLocatorImpl (int lineNumber, int columnNumber, int offset, Node errorNode, String uri )


  /**
   * The line number where the error occured, or -1 if there is no line
   * number available.
   */
   public int getLineNumber(){
        return fLineNumber;
   }

  /**
   * The column number where the error occured, or -1 if there is no column
   * number available.
   */
  public int getColumnNumber(){
        return fColumnNumber;
  }


  /**
   * The URI where the error occured, or null if there is no URI available.
   */
  public String getUri(){
        return fUri;
  }


  public Node getRelatedNode(){
    return fRelatedNode;
  }


  /**
   * The byte offset into the input source this locator is pointing to or -1
   * if there is no byte offset available
   */
  public int getByteOffset(){
        return fByteOffset;
  }

  /**
   * The UTF-16, as defined in [Unicode] and Amendment 1 of [ISO/IEC 10646],
   * offset into the input source this locator is pointing to or -1 if there
   * is no UTF-16 offset available.
   */
  public int getUtf16Offset(){
        return fUtf16Offset;
  }

}// class DOMLocatorImpl

⏎ com/sun/org/apache/xerces/internal/dom/DOMLocatorImpl.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
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