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/StreamPrintService.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.print;

import java.io.OutputStream;

/**
 * This class extends {@link PrintService} and represents a
 * print service that prints data in different formats to a
 * client-provided output stream.
 * This is principally intended for services where
 * the output format is a document type suitable for viewing
 * or archiving.
 * The output format must be declared as a mime type.
 * This is equivalent to an output document flavor where the
 * representation class is always "java.io.OutputStream"
 * An instance of the <code>StreamPrintService</code> class is
 * obtained from a {@link StreamPrintServiceFactory} instance.
 * <p>
 * Note that a <code>StreamPrintService</code> is different from a
 * <code>PrintService</code>, which supports a
 * {@link javax.print.attribute.standard.Destination Destination}
 * attribute.  A <code>StreamPrintService</code> always requires an output
 * stream, whereas a <code>PrintService</code> optionally accepts a
 * <code>Destination</code>. A <code>StreamPrintService</code>
 * has no default destination for its formatted output.
 * Additionally a <code>StreamPrintService</code> is expected to generate
output in
 * a format useful in other contexts.
 * StreamPrintService's are not expected to support the Destination attribute.
 */

public abstract class StreamPrintService implements PrintService {

    private OutputStream outStream;
    private boolean disposed = false;

    private StreamPrintService() {
    };

    /**
     * Constructs a StreamPrintService object.
     *
     * @param out  stream to which to send formatted print data.
     */
    protected StreamPrintService(OutputStream out) {
        this.outStream = out;
    }

    /**
     * Gets the output stream.
     *
     * @return the stream to which this service will send formatted print data.
     */
    public OutputStream getOutputStream() {
        return outStream;
    }

    /**
     * Returns the document format emitted by this print service.
     * Must be in mimetype format, compatible with the mime type
     * components of DocFlavors @see DocFlavor.
     * @return mime type identifying the output format.
     */
    public abstract String getOutputFormat();

    /**
     * Disposes this <code>StreamPrintService</code>.
     * If a stream service cannot be re-used, it must be disposed
     * to indicate this. Typically the client will call this method.
     * Services which write data which cannot meaningfully be appended to
     * may also dispose the stream. This does not close the stream. It
     * just marks it as not for further use by this service.
     */
    public void dispose() {
        disposed = true;
    }

    /**
     * Returns a <code>boolean</code> indicating whether or not
     * this <code>StreamPrintService</code> has been disposed.
     * If this object has been disposed, will return true.
     * Used by services and client applications to recognize streams
     * to which no further data should be written.
     * @return if this <code>StreamPrintService</code> has been disposed
     */
    public boolean isDisposed() {
        return disposed;
    }

}

⏎ javax/print/StreamPrintService.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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