Home » openjdk-7 » java » awt » image » [javadoc | source]

    1   /*
    2    * Copyright (c) 1995, 2000, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   
   26   package java.awt.image;
   27   
   28   /**
   29    * The interface for objects which can produce the image data for Images.
   30    * Each image contains an ImageProducer which is used to reconstruct
   31    * the image whenever it is needed, for example, when a new size of the
   32    * Image is scaled, or when the width or height of the Image is being
   33    * requested.
   34    *
   35    * @see ImageConsumer
   36    *
   37    * @author      Jim Graham
   38    */
   39   public interface ImageProducer {
   40       /**
   41        * Registers an <code>ImageConsumer</code> with the
   42        * <code>ImageProducer</code> for access to the image data
   43        * during a later reconstruction of the <code>Image</code>.
   44        * The <code>ImageProducer</code> may, at its discretion,
   45        * start delivering the image data to the consumer
   46        * using the <code>ImageConsumer</code> interface immediately,
   47        * or when the next available image reconstruction is triggered
   48        * by a call to the <code>startProduction</code> method.
   49        * @param ic the specified <code>ImageConsumer</code>
   50        * @see #startProduction
   51        */
   52       public void addConsumer(ImageConsumer ic);
   53   
   54       /**
   55        * Determines if a specified <code>ImageConsumer</code>
   56        * object is currently registered with this
   57        * <code>ImageProducer</code> as one of its consumers.
   58        * @param ic the specified <code>ImageConsumer</code>
   59        * @return <code>true</code> if the specified
   60        *         <code>ImageConsumer</code> is registered with
   61        *         this <code>ImageProducer</code>;
   62        *         <code>false</code> otherwise.
   63        */
   64       public boolean isConsumer(ImageConsumer ic);
   65   
   66       /**
   67        * Removes the specified <code>ImageConsumer</code> object
   68        * from the list of consumers currently registered to
   69        * receive image data.  It is not considered an error
   70        * to remove a consumer that is not currently registered.
   71        * The <code>ImageProducer</code> should stop sending data
   72        * to this consumer as soon as is feasible.
   73        * @param ic the specified <code>ImageConsumer</code>
   74        */
   75       public void removeConsumer(ImageConsumer ic);
   76   
   77       /**
   78        * Registers the specified <code>ImageConsumer</code> object
   79        * as a consumer and starts an immediate reconstruction of
   80        * the image data which will then be delivered to this
   81        * consumer and any other consumer which might have already
   82        * been registered with the producer.  This method differs
   83        * from the addConsumer method in that a reproduction of
   84        * the image data should be triggered as soon as possible.
   85        * @param ic the specified <code>ImageConsumer</code>
   86        * @see #addConsumer
   87        */
   88       public void startProduction(ImageConsumer ic);
   89   
   90       /**
   91        * Requests, on behalf of the <code>ImageConsumer</code>,
   92        * that the <code>ImageProducer</code> attempt to resend
   93        * the image data one more time in TOPDOWNLEFTRIGHT order
   94        * so that higher quality conversion algorithms which
   95        * depend on receiving pixels in order can be used to
   96        * produce a better output version of the image.  The
   97        * <code>ImageProducer</code> is free to
   98        * ignore this call if it cannot resend the data in that
   99        * order.  If the data can be resent, the
  100        * <code>ImageProducer</code> should respond by executing
  101        * the following minimum set of <code>ImageConsumer</code>
  102        * method calls:
  103        * <pre>
  104        *  ic.setHints(TOPDOWNLEFTRIGHT | < otherhints >);
  105        *  ic.setPixels(...);      // As many times as needed
  106        *  ic.imageComplete();
  107        * </pre>
  108        * @param ic the specified <code>ImageConsumer</code>
  109        * @see ImageConsumer#setHints
  110        */
  111       public void requestTopDownLeftRightResend(ImageConsumer ic);
  112   }

Home » openjdk-7 » java » awt » image » [javadoc | source]