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/Paint.java

/*
 * Copyright (c) 1997, 2008, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.awt;

import java.awt.image.ColorModel;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;

/**
 * This <code>Paint</code> interface defines how color patterns
 * can be generated for {@link Graphics2D} operations.  A class
 * implementing the <code>Paint</code> interface is added to the
 * <code>Graphics2D</code> context in order to define the color
 * pattern used by the <code>draw</code> and <code>fill</code> methods.
 * <p>
 * Instances of classes implementing <code>Paint</code> must be
 * read-only because the <code>Graphics2D</code> does not clone
 * these objects when they are set as an attribute with the
 * <code>setPaint</code> method or when the <code>Graphics2D</code>
 * object is itself cloned.
 * @see PaintContext
 * @see Color
 * @see GradientPaint
 * @see TexturePaint
 * @see Graphics2D#setPaint
 * @version 1.36, 06/05/07
 */

public interface Paint extends Transparency {
    /**
     * Creates and returns a {@link PaintContext} used to
     * generate the color pattern.
     * The arguments to this method convey additional information
     * about the rendering operation that may be
     * used or ignored on various implementations of the {@code Paint} interface.
     * A caller must pass non-{@code null} values for all of the arguments
     * except for the {@code ColorModel} argument which may be {@code null} to
     * indicate that no specific {@code ColorModel} type is preferred.
     * Implementations of the {@code Paint} interface are allowed to use or ignore
     * any of the arguments as makes sense for their function, and are
     * not constrained to use the specified {@code ColorModel} for the returned
     * {@code PaintContext}, even if it is not {@code null}.
     * Implementations are allowed to throw {@code NullPointerException} for
     * any {@code null} argument other than the {@code ColorModel} argument,
     * but are not required to do so.
     *
     * @param cm the preferred {@link ColorModel} which represents the most convenient
     *           format for the caller to receive the pixel data, or {@code null}
     *           if there is no preference.
     * @param deviceBounds the device space bounding box
     *                     of the graphics primitive being rendered.
     *                     Implementations of the {@code Paint} interface
     *                     are allowed to throw {@code NullPointerException}
     *                     for a {@code null} {@code deviceBounds}.
     * @param userBounds the user space bounding box
     *                   of the graphics primitive being rendered.
     *                     Implementations of the {@code Paint} interface
     *                     are allowed to throw {@code NullPointerException}
     *                     for a {@code null} {@code userBounds}.
     * @param xform the {@link AffineTransform} from user
     *              space into device space.
     *                     Implementations of the {@code Paint} interface
     *                     are allowed to throw {@code NullPointerException}
     *                     for a {@code null} {@code xform}.
     * @param hints the set of hints that the context object can use to
     *              choose between rendering alternatives.
     *                     Implementations of the {@code Paint} interface
     *                     are allowed to throw {@code NullPointerException}
     *                     for a {@code null} {@code hints}.
     * @return the {@code PaintContext} for
     *         generating color patterns.
     * @see PaintContext
     * @see ColorModel
     * @see Rectangle
     * @see Rectangle2D
     * @see AffineTransform
     * @see RenderingHints
     */
    public PaintContext createContext(ColorModel cm,
                                      Rectangle deviceBounds,
                                      Rectangle2D userBounds,
                                      AffineTransform xform,
                                      RenderingHints hints);

}

⏎ java/awt/Paint.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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