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/xpath/XPathExpression.java

/*
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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/*
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 * Copyright (c) 2002 World Wide Web Consortium,
 * (Massachusetts Institute of Technology, Institut National de
 * Recherche en Informatique et en Automatique, Keio University). All
 * Rights Reserved. This program is distributed under the W3C's Software
 * Intellectual Property License. This program is distributed 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.
 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
 */

package org.w3c.dom.xpath;


import org.w3c.dom.Node;
import org.w3c.dom.DOMException;

/**
 * The <code>XPathExpression</code> interface represents a parsed and resolved
 * XPath expression.
 * <p>See also the <a href='http://www.w3.org/2002/08/WD-DOM-Level-3-XPath-20020820'>Document Object Model (DOM) Level 3 XPath Specification</a>.
 */
public interface XPathExpression {
    /**
     * Evaluates this XPath expression and returns a result.
     * @param contextNode The <code>context</code> is context node for the
     *   evaluation of this XPath expression.If the XPathEvaluator was
     *   obtained by casting the <code>Document</code> then this must be
     *   owned by the same document and must be a <code>Document</code>,
     *   <code>Element</code>, <code>Attribute</code>, <code>Text</code>,
     *   <code>CDATASection</code>, <code>Comment</code>,
     *   <code>ProcessingInstruction</code>, or <code>XPathNamespace</code>
     *   node.If the context node is a <code>Text</code> or a
     *   <code>CDATASection</code>, then the context is interpreted as the
     *   whole logical text node as seen by XPath, unless the node is empty
     *   in which case it may not serve as the XPath context.
     * @param type If a specific <code>type</code> is specified, then the
     *   result will be coerced to return the specified type relying on
     *   XPath conversions and fail if the desired coercion is not possible.
     *   This must be one of the type codes of <code>XPathResult</code>.
     * @param result The <code>result</code> specifies a specific result
     *   object which may be reused and returned by this method. If this is
     *   specified as <code>null</code>or the implementation does not reuse
     *   the specified result, a new result object will be constructed and
     *   returned.For XPath 1.0 results, this object will be of type
     *   <code>XPathResult</code>.
     * @return The result of the evaluation of the XPath expression.For XPath
     *   1.0 results, this object will be of type <code>XPathResult</code>.
     * @exception XPathException
     *   TYPE_ERR: Raised if the result cannot be converted to return the
     *   specified type.
     * @exception DOMException
     *   WRONG_DOCUMENT_ERR: The Node is from a document that is not supported
     *   by the XPathEvaluator that created this <code>XPathExpression</code>
     *   .
     *   <br>NOT_SUPPORTED_ERR: The Node is not a type permitted as an XPath
     *   context node or the request type is not permitted by this
     *   <code>XPathExpression</code>.
     */
    public Object evaluate(Node contextNode,
                           short type,
                           Object result)
                           throws XPathException, DOMException;

}

⏎ org/w3c/dom/xpath/XPathExpression.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

⇑ Download and Use JDK 8

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