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/ConnectionEventListener.java

/*
 * Copyright (c) 2000, 2001, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.sql;

/**
 * <P>
 * An object that registers to be notified of events generated by a
 * <code>PooledConnection</code> object.
 * <P>
 * The <code>ConnectionEventListener</code> interface is implemented by a
 * connection pooling component.  A connection pooling component will
 * usually be provided by a JDBC driver vendor or another system software
 * vendor.  A JDBC driver notifies a <code>ConnectionEventListener</code>
 * object when an application is finished using a pooled connection with
 * which the listener has registered.  The notification
 * occurs after the application calls the method <code>close</code> on
 * its representation of a <code>PooledConnection</code> object.  A
 * <code>ConnectionEventListener</code> is also notified when a
 * connection error occurs due to the fact that the <code>PooledConnection</code>
 * is unfit for future use---the server has crashed, for example.
 * The listener is notified by the JDBC driver just before the driver throws an
 * <code>SQLException</code> to the application using the
 * <code>PooledConnection</code> object.
 *
 * @since 1.4
 */

public interface ConnectionEventListener extends java.util.EventListener {

  /**
   * Notifies this <code>ConnectionEventListener</code> that
   * the application has called the method <code>close</code> on its
   * representation of a pooled connection.
   *
   * @param event an event object describing the source of
   * the event
   */
  void connectionClosed(ConnectionEvent event);

  /**
   * Notifies this <code>ConnectionEventListener</code> that
   * a fatal error has occurred and the pooled connection can
   * no longer be used.  The driver makes this notification just
   * before it throws the application the <code>SQLException</code>
   * contained in the given <code>ConnectionEvent</code> object.
   *
   * @param event an event object describing the source of
   * the event and containing the <code>SQLException</code> that the
   * driver is about to throw
   */
  void connectionErrorOccurred(ConnectionEvent event);

 }

⏎ javax/sql/ConnectionEventListener.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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