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 org.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ org/w3c/dom/DOMErrorHandler.java

/*
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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/*
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 * Copyright (c) 2004 World Wide Web Consortium,
 *
 * (Massachusetts Institute of Technology, European Research Consortium for
 * Informatics and Mathematics, Keio University). All Rights Reserved. This
 * work is distributed under the W3C(r) Software License [1] in the hope that
 * it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231
 */

package org.w3c.dom;

/**
 *  <code>DOMErrorHandler</code> is a callback interface that the DOM
 * implementation can call when reporting errors that happens while
 * processing XML data, or when doing some other processing (e.g. validating
 * a document). A <code>DOMErrorHandler</code> object can be attached to a
 * <code>Document</code> using the "error-handler" on the
 * <code>DOMConfiguration</code> interface. If more than one error needs to
 * be reported during an operation, the sequence and numbers of the errors
 * passed to the error handler are implementation dependent.
 * <p> The application that is using the DOM implementation is expected to
 * implement this interface.
 * <p>See also the <a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>Document Object Model (DOM) Level 3 Core Specification</a>.
 * @since DOM Level 3
 */
public interface DOMErrorHandler {
    /**
     * This method is called on the error handler when an error occurs.
     * <br> If an exception is thrown from this method, it is considered to be
     * equivalent of returning <code>true</code>.
     * @param error  The error object that describes the error. This object
     *   may be reused by the DOM implementation across multiple calls to
     *   the <code>handleError</code> method.
     * @return  If the <code>handleError</code> method returns
     *   <code>false</code>, the DOM implementation should stop the current
     *   processing when possible. If the method returns <code>true</code>,
     *   the processing may continue depending on
     *   <code>DOMError.severity</code>.
     */
    public boolean handleError(DOMError error);

}

⏎ org/w3c/dom/DOMErrorHandler.java

Or download all of them as a single archive file:

File name: jre-rt-org-1.8.0_191-src.zip
File size: 951125 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - com.* Package Source Code

⇐ JRE 8 rt.jar - javax.* Package Source Code

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