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 * particular file as subject to the "Classpath" exception as provided

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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

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package java.awt;

import java.awt.image.ColorModel;

/**

 * The <code>Composite</code> interface, along with

 * {@link CompositeContext}, defines the methods to compose a draw

 * primitive with the underlying graphics area.

 * After the <code>Composite</code> is set in the

 * {@link Graphics2D} context, it combines a shape, text, or an image

 * being rendered with the colors that have already been rendered

 * according to pre-defined rules. The classes

 * implementing this interface provide the rules and a method to create

 * the context for a particular operation.

 * <code>CompositeContext</code> is an environment used by the

 * compositing operation, which is created by the <code>Graphics2D</code>

 * prior to the start of the operation.  <code>CompositeContext</code>

 * contains private information and resources needed for a compositing

 * operation.  When the <code>CompositeContext</code> is no longer needed,

 * the <code>Graphics2D</code> object disposes of it in order to reclaim

 * resources allocated for the operation.

 * <p>

 * Instances of classes implementing <code>Composite</code> must be

 * immutable because the <code>Graphics2D</code> does not clone

 * these objects when they are set as an attribute with the

 * <code>setComposite</code> method or when the <code>Graphics2D</code>

 * object is cloned.  This is to avoid undefined rendering behavior of

 * <code>Graphics2D</code>, resulting from the modification of

 * the <code>Composite</code> object after it has been set in the

 * <code>Graphics2D</code> context.

 * <p>

 * Since this interface must expose the contents of pixels on the

 * target device or image to potentially arbitrary code, the use of

 * custom objects which implement this interface when rendering directly

 * to a screen device is governed by the <code>readDisplayPixels</code>

 * {@link AWTPermission}.  The permission check will occur when such

 * a custom object is passed to the <code>setComposite</code> method

 * of a <code>Graphics2D</code> retrieved from a {@link Component}.

 * @see AlphaComposite

 * @see CompositeContext

 * @see Graphics2D#setComposite

 */

public interface Composite {

    /**

     * Creates a context containing state that is used to perform

     * the compositing operation.  In a multi-threaded environment,

     * several contexts can exist simultaneously for a single

     * <code>Composite</code> object.

     * @param srcColorModel  the {@link ColorModel} of the source

     * @param dstColorModel  the <code>ColorModel</code> of the destination

     * @param hints the hint that the context object uses to choose between

     * rendering alternatives

     * @return the <code>CompositeContext</code> object used to perform the

     * compositing operation.

     */

    public CompositeContext createContext(ColorModel srcColorModel,

                                          ColorModel dstColorModel,

                                          RenderingHints hints);

}