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	/*
	* Copyright (c) 2000, 2013, 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 javax.imageio.event;

	import java.util.EventListener;
	import javax.imageio.ImageReader;

	/**
	* An interface used by <code>ImageReader</code> implementations to
	* notify callers of their image and thumbnail reading methods of
	* progress.
	*
	* <p> This interface receives general indications of decoding
	* progress (via the <code>imageProgress</code> and
	* <code>thumbnailProgress</code> methods), and events indicating when
	* an entire image has been updated (via the
	* <code>imageStarted</code>, <code>imageComplete</code>,
	* <code>thumbnailStarted</code> and <code>thumbnailComplete</code>
	* methods). Applications that wish to be informed of pixel updates
	* as they happen (for example, during progressive decoding), should
	* provide an <code>IIOReadUpdateListener</code>.
	*
	* @see IIOReadUpdateListener
	* @see javax.imageio.ImageReader#addIIOReadProgressListener
	* @see javax.imageio.ImageReader#removeIIOReadProgressListener
	*
	*/
	public interface IIOReadProgressListener extends EventListener {

	/**
	* Reports that a sequence of read operations is beginning.
	* <code>ImageReader</code> implementations are required to call
	* this method exactly once from their
	* <code>readAll(Iterator)</code> method.
	*
	* @param source the <code>ImageReader</code> object calling this method.
	* @param minIndex the index of the first image to be read.
	*/
	void sequenceStarted(ImageReader source, int minIndex);

	/**
	* Reports that a sequence of read operations has completed.
	* <code>ImageReader</code> implementations are required to call
	* this method exactly once from their
	* <code>readAll(Iterator)</code> method.
	*
	* @param source the <code>ImageReader</code> object calling this method.
	*/
	void sequenceComplete(ImageReader source);

	/**
	* Reports that an image read operation is beginning. All
	* <code>ImageReader</code> implementations are required to call
	* this method exactly once when beginning an image read
	* operation.
	*
	* @param source the <code>ImageReader</code> object calling this method.
	* @param imageIndex the index of the image being read within its
	* containing input file or stream.
	*/
	void imageStarted(ImageReader source, int imageIndex);

	/**
	* Reports the approximate degree of completion of the current
	* <code>read</code> call of the associated
	* <code>ImageReader</code>.
	*
	* <p> The degree of completion is expressed as a percentage
	* varying from <code>0.0F</code> to <code>100.0F</code>. The
	* percentage should ideally be calculated in terms of the
	* remaining time to completion, but it is usually more practical
	* to use a more well-defined metric such as pixels decoded or
	* portion of input stream consumed. In any case, a sequence of
	* calls to this method during a given read operation should
	* supply a monotonically increasing sequence of percentage
	* values. It is not necessary to supply the exact values
	* <code>0</code> and <code>100</code>, as these may be inferred
	* by the callee from other methods.
	*
	* <p> Each particular <code>ImageReader</code> implementation may
	* call this method at whatever frequency it desires. A rule of
	* thumb is to call it around each 5 percent mark.
	*
	* @param source the <code>ImageReader</code> object calling this method.
	* @param percentageDone the approximate percentage of decoding that
	* has been completed.
	*/
	void imageProgress(ImageReader source, float percentageDone);

	/**
	* Reports that the current image read operation has completed.
	* All <code>ImageReader</code> implementations are required to
	* call this method exactly once upon completion of each image
	* read operation.
	*
	* @param source the <code>ImageReader</code> object calling this
	* method.
	*/
	void imageComplete(ImageReader source);

	/**
	* Reports that a thumbnail read operation is beginning. All
	* <code>ImageReader</code> implementations are required to call
	* this method exactly once when beginning a thumbnail read
	* operation.
	*
	* @param source the <code>ImageReader</code> object calling this method.
	* @param imageIndex the index of the image being read within its
	* containing input file or stream.
	* @param thumbnailIndex the index of the thumbnail being read.
	*/
	void thumbnailStarted(ImageReader source,
	int imageIndex, int thumbnailIndex);

	/**
	* Reports the approximate degree of completion of the current
	* <code>getThumbnail</code> call within the associated
	* <code>ImageReader</code>. The semantics are identical to those
	* of <code>imageProgress</code>.
	*
	* @param source the <code>ImageReader</code> object calling this method.
	* @param percentageDone the approximate percentage of decoding that
	* has been completed.
	*/
	void thumbnailProgress(ImageReader source, float percentageDone);

	/**
	* Reports that a thumbnail read operation has completed. All
	* <code>ImageReader</code> implementations are required to call
	* this method exactly once upon completion of each thumbnail read
	* operation.
	*
	* @param source the <code>ImageReader</code> object calling this
	* method.
	*/
	void thumbnailComplete(ImageReader source);

	/**
	* Reports that a read has been aborted via the reader's
	* <code>abort</code> method. No further notifications will be
	* given.
	*
	* @param source the <code>ImageReader</code> object calling this
	* method.
	*/
	void readAborted(ImageReader source);
	}

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