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 java.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ java/awt/print/Pageable.java

/*
 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
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 *
 *
 *
 *
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 *
 *
 *
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 *
 *
 */

package java.awt.print;

import java.lang.annotation.Native;

/**
 * The <code>Pageable</code> implementation represents a set of
 * pages to be printed. The <code>Pageable</code> object returns
 * the total number of pages in the set as well as the
 * {@link PageFormat} and {@link Printable} for a specified page.
 * @see java.awt.print.PageFormat
 * @see java.awt.print.Printable
 */
public interface Pageable {

    /**
     * This constant is returned from the
     * {@link #getNumberOfPages() getNumberOfPages}
     * method if a <code>Pageable</code> implementation does not know
     * the number of pages in its set.
     */
    @Native int UNKNOWN_NUMBER_OF_PAGES = -1;

    /**
     * Returns the number of pages in the set.
     * To enable advanced printing features,
     * it is recommended that <code>Pageable</code>
     * implementations return the true number of pages
     * rather than the
     * UNKNOWN_NUMBER_OF_PAGES constant.
     * @return the number of pages in this <code>Pageable</code>.
     */
    int getNumberOfPages();

    /**
     * Returns the <code>PageFormat</code> of the page specified by
     * <code>pageIndex</code>.
     * @param pageIndex the zero based index of the page whose
     *            <code>PageFormat</code> is being requested
     * @return the <code>PageFormat</code> describing the size and
     *          orientation.
     * @throws IndexOutOfBoundsException if
     *          the <code>Pageable</code> does not contain the requested
     *          page.
     */
    PageFormat getPageFormat(int pageIndex)
        throws IndexOutOfBoundsException;

    /**
     * Returns the <code>Printable</code> instance responsible for
     * rendering the page specified by <code>pageIndex</code>.
     * @param pageIndex the zero based index of the page whose
     *            <code>Printable</code> is being requested
     * @return the <code>Printable</code> that renders the page.
     * @throws IndexOutOfBoundsException if
     *            the <code>Pageable</code> does not contain the requested
     *            page.
     */
    Printable getPrintable(int pageIndex)
        throws IndexOutOfBoundsException;
}

⏎ java/awt/print/Pageable.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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