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/sound/midi/MetaEventListener.java

/*
 * Copyright (c) 1999, 2002, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.sound.midi;

import java.util.EventListener;


/**
 * The <code>MetaEventListener</code> interface should be implemented
 * by classes whose instances need to be notified when a <code>{@link Sequencer}</code>
 * has processed a <code>{@link MetaMessage}</code>.
 * To register a <code>MetaEventListener</code> object to receive such
 * notifications, pass it as the argument to the
 * <code>{@link Sequencer#addMetaEventListener(MetaEventListener) addMetaEventListener}</code>
 * method of <code>Sequencer</code>.
 *
 * @author Kara Kytle
 */
public interface MetaEventListener extends EventListener {

    /**
     * Invoked when a <code>{@link Sequencer}</code> has encountered and processed
     * a <code>MetaMessage</code> in the <code>{@link Sequence}</code> it is processing.
     * @param meta the meta-message that the sequencer encountered
     */
    public void meta(MetaMessage meta);
}

⏎ javax/sound/midi/MetaEventListener.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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