/* * Copyright (c) 1995, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * 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). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.awt.image; import java.util.Hashtable; /** * This class implements a filter for the set of interface methods that * are used to deliver data from an ImageProducer to an ImageConsumer. * It is meant to be used in conjunction with a FilteredImageSource * object to produce filtered versions of existing images. It is a * base class that provides the calls needed to implement a "Null filter" * which has no effect on the data being passed through. Filters should * subclass this class and override the methods which deal with the * data that needs to be filtered and modify it as necessary. * * @see FilteredImageSource * @see ImageConsumer * * @author Jim Graham */ public class ImageFilter implements ImageConsumer, Cloneable { /** * The consumer of the particular image data stream for which this * instance of the ImageFilter is filtering data. It is not * initialized during the constructor, but rather during the * getFilterInstance() method call when the FilteredImageSource * is creating a unique instance of this object for a particular * image data stream. * @see #getFilterInstance * @see ImageConsumer */ protected ImageConsumer consumer; /** * Returns a unique instance of an ImageFilter object which will * actually perform the filtering for the specified ImageConsumer. * The default implementation just clones this object. *
* Note: This method is intended to be called by the ImageProducer * of the Image whose pixels are being filtered. Developers using * this class to filter pixels from an image should avoid calling * this method directly since that operation could interfere * with the filtering operation. * @param ic the specified {@code ImageConsumer} * @return an {@code ImageFilter} used to perform the * filtering for the specified {@code ImageConsumer}. */ public ImageFilter getFilterInstance(ImageConsumer ic) { ImageFilter instance = (ImageFilter) clone(); instance.consumer = ic; return instance; } /** * Returns a unique instance of an ImageFilter object used to perform * the filtering for an image which size is scaled (relative to * the original image size). * The default implementation just clones this object. *
* @param scaleX the specified scale factor fox x-axis * @param scaleY the specified scale factor fox y-axis * @return an {@code ImageFilter} used to perform the * filtering for scaled images. */ public ImageFilter getScaledFilterInstance(double scaleX, double scaleY) { return (ImageFilter) clone(); } /** * Filters the information provided in the setDimensions method * of the ImageConsumer interface. *
* Note: This method is intended to be called by the ImageProducer * of the Image whose pixels are being filtered. Developers using * this class to filter pixels from an image should avoid calling * this method directly since that operation could interfere * with the filtering operation. * @see ImageConsumer#setDimensions */ public void setDimensions(int width, int height) { consumer.setDimensions(width, height); } /** * Passes the properties from the source object along after adding a * property indicating the stream of filters it has been run through. *
* Note: This method is intended to be called by the ImageProducer * of the Image whose pixels are being filtered. Developers using * this class to filter pixels from an image should avoid calling * this method directly since that operation could interfere * with the filtering operation. * * @param props the properties from the source object * @exception NullPointerException if {@code props} is null */ public void setProperties(Hashtable,?> props) { @SuppressWarnings("unchecked") Hashtable