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/XADataSource.java

/*
 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.sql;

import java.sql.*;

/**
 * A factory for {@code XAConnection} objects that is used internally.
 * An object that implements the {@code XADataSource} interface is
 * typically registered with a naming service that uses the
 * Java Naming and Directory Interface™
 * (JNDI).
 *  <p>
 * An implementation of {@code XADataSource} must include a public no-arg
 * constructor.
 * @since 1.4
 */

public interface XADataSource extends CommonDataSource {

  /**
   * Attempts to establish a physical database connection that can be
   * used in a distributed transaction.
   *
   * @return  an {@code XAConnection} object, which represents a
   *          physical connection to a data source, that can be used in
   *          a distributed transaction
   * @exception SQLException if a database access error occurs
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @throws SQLTimeoutException when the driver has determined that the
   * timeout value specified by the {@code setLoginTimeout} method
   * has been exceeded and has at least tried to cancel the
   * current database connection attempt
   * @since 1.4
   */
  XAConnection getXAConnection() throws SQLException;

  /**
   * Attempts to establish a physical database connection, using the given
   * user name and password. The connection that is returned is one that
   * can be used in a distributed transaction.
   *
   * @param user the database user on whose behalf the connection is being made
   * @param password the user's password
   * @return  an {@code XAConnection} object, which represents a
   *          physical connection to a data source, that can be used in
   *          a distributed transaction
   * @exception SQLException if a database access error occurs
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @throws SQLTimeoutException when the driver has determined that the
   * timeout value specified by the {@code setLoginTimeout} method
   * has been exceeded and has at least tried to cancel the
   * current database connection attempt
   * @since 1.4
   */
  XAConnection getXAConnection(String user, String password)
    throws SQLException;
 }

⏎ javax/sql/XADataSource.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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