/*
* @(#)ImageProducer.java 1.21 05/11/17
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.awt.image;
/**
* The interface for objects which can produce the image data for Images.
* Each image contains an ImageProducer which is used to reconstruct
* the image whenever it is needed, for example, when a new size of the
* Image is scaled, or when the width or height of the Image is being
* requested.
*
* @see ImageConsumer
*
* @version 1.21 11/17/05
* @author Jim Graham
*/
public interface ImageProducer {
/**
* Registers an <code>ImageConsumer</code> with the
* <code>ImageProducer</code> for access to the image data
* during a later reconstruction of the <code>Image</code>.
* The <code>ImageProducer</code> may, at its discretion,
* start delivering the image data to the consumer
* using the <code>ImageConsumer</code> interface immediately,
* or when the next available image reconstruction is triggered
* by a call to the <code>startProduction</code> method.
* @param ic the specified <code>ImageConsumer</code>
* @see #startProduction
*/
public void addConsumer(ImageConsumer ic);
/**
* Determines if a specified <code>ImageConsumer</code>
* object is currently registered with this
* <code>ImageProducer</code> as one of its consumers.
* @param ic the specified <code>ImageConsumer</code>
* @return <code>true</code> if the specified
* <code>ImageConsumer</code> is registered with
* this <code>ImageProducer</code>;
* <code>false</code> otherwise.
*/
public boolean isConsumer(ImageConsumer ic);
/**
* Removes the specified <code>ImageConsumer</code> object
* from the list of consumers currently registered to
* receive image data. It is not considered an error
* to remove a consumer that is not currently registered.
* The <code>ImageProducer</code> should stop sending data
* to this consumer as soon as is feasible.
* @param ic the specified <code>ImageConsumer</code>
*/
public void removeConsumer(ImageConsumer ic);
/**
* Registers the specified <code>ImageConsumer</code> object
* as a consumer and starts an immediate reconstruction of
* the image data which will then be delivered to this
* consumer and any other consumer which might have already
* been registered with the producer. This method differs
* from the addConsumer method in that a reproduction of
* the image data should be triggered as soon as possible.
* @param ic the specified <code>ImageConsumer</code>
* @see #addConsumer
*/
public void startProduction(ImageConsumer ic);
/**
* Requests, on behalf of the <code>ImageConsumer</code>,
* that the <code>ImageProducer</code> attempt to resend
* the image data one more time in TOPDOWNLEFTRIGHT order
* so that higher quality conversion algorithms which
* depend on receiving pixels in order can be used to
* produce a better output version of the image. The
* <code>ImageProducer</code> is free to
* ignore this call if it cannot resend the data in that
* order. If the data can be resent, the
* <code>ImageProducer</code> should respond by executing
* the following minimum set of <code>ImageConsumer</code>
* method calls:
* <pre>
* ic.setHints(TOPDOWNLEFTRIGHT | < otherhints >);
* ic.setPixels(...); // As many times as needed
* ic.imageComplete();
* </pre>
* @param ic the specified <code>ImageConsumer</code>
* @see ImageConsumer#setHints
*/
public void requestTopDownLeftRightResend(ImageConsumer ic);
}