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/print/event/PrintServiceAttributeEvent.java

/*
 * Copyright (c) 2000, 2003, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package javax.print.event;

import javax.print.PrintService;
import javax.print.attribute.AttributeSetUtilities;
import javax.print.attribute.PrintServiceAttributeSet;

/**
 *
 * Class PrintServiceAttributeEvent encapsulates an event a
 * Print Service instance reports to let the client know of
 * changes in the print service state.
 */

public class PrintServiceAttributeEvent extends PrintEvent {

    private static final long serialVersionUID = -7565987018140326600L;

    private PrintServiceAttributeSet attributes;

    /**
     * Constructs a PrintServiceAttributeEvent object.
     *
     * @param source the print job generating  this event
     * @param attributes the attribute changes being reported
     * @throws IllegalArgumentException if <code>source</code> is
     *         <code>null</code>.
     */
    public PrintServiceAttributeEvent(PrintService source,
                                      PrintServiceAttributeSet attributes) {

        super(source);
        this.attributes = AttributeSetUtilities.unmodifiableView(attributes);
    }


    /**
     * Returns the print service.

     * @return  Print Service object.
     */
    public PrintService getPrintService() {

        return (PrintService) getSource();
    }


    /**
     * Determine the printing service attributes that changed and their new
     * values.
     *
     * @return  Attributes containing the new values for the service
     * attributes that changed. The returned set may be unmodifiable.
     */
    public PrintServiceAttributeSet getAttributes() {

        return attributes;
    }

}

⏎ javax/print/event/PrintServiceAttributeEvent.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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