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

⏎ javax/sql/rowset/spi/XmlWriter.java

/*
 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 *
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 */

package javax.sql.rowset.spi;

import java.sql.SQLException;
import java.io.Writer;

import javax.sql.RowSetWriter;
import javax.sql.rowset.*;

/**
 * A specialized interface that facilitates an extension of the
 * <code>SyncProvider</code> abstract class for XML orientated
 * synchronization providers.
 * <p>
 * <code>SyncProvider</code>  implementations that supply XML data writer
 * capabilities such as output XML stream capabilities can implement this
 * interface to provide standard <code>XmlWriter</code> objects to
 * <code>WebRowSet</code> implementations.
 * <P>
 * Writing a <code>WebRowSet</code> object includes printing the
 * rowset's data, metadata, and properties, all with the
 * appropriate XML tags.
 */
public interface XmlWriter extends RowSetWriter {

  /**
   * Writes the given <code>WebRowSet</code> object to the specified
   * <code>java.io.Writer</code> output stream as an XML document.
   * This document includes the rowset's data, metadata, and properties
   * plus the appropriate XML tags.
   * <P>
   * The <code>caller</code> parameter must be a <code>WebRowSet</code>
   * object whose <code>XmlWriter</code> field contains a reference to
   * this <code>XmlWriter</code> object.
   *
   * @param caller the <code>WebRowSet</code> instance to be written,
   *        for which this <code>XmlWriter</code> object is the writer
   * @param writer the <code>java.io.Writer</code> object that serves
   *        as the output stream for writing <code>caller</code> as
   *        an XML document
   * @throws SQLException if a database access error occurs or
   *            this <code>XmlWriter</code> object is not the writer
   *            for the given <code>WebRowSet</code> object
   */
  public void writeXML(WebRowSet caller, java.io.Writer writer)
    throws SQLException;



}

⏎ javax/sql/rowset/spi/XmlWriter.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

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

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

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