ImageDecoderImpl.java
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- /*
- * Copyright (c) 2001 Sun Microsystems, Inc. All Rights Reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * -Redistributions of source code must retain the above copyright notice, this
- * list of conditions and the following disclaimer.
- *
- * -Redistribution in binary form must reproduct the above copyright notice,
- * this list of conditions and the following disclaimer in the documentation
- * and/or other materials provided with the distribution.
- *
- * Neither the name of Sun Microsystems, Inc. or the names of contributors may
- * be used to endorse or promote products derived from this software without
- * specific prior written permission.
- *
- * This software is provided "AS IS," without a warranty of any kind. ALL
- * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY
- * IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
- * NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE
- * LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING
- * OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS
- * LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT,
- * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER
- * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF
- * OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGES.
- *
- * You acknowledge that Software is not designed,licensed or intended for use in
- * the design, construction, operation or maintenance of any nuclear facility.
- */
- import java.awt.image.Raster;
- import java.awt.image.RenderedImage;
- import java.io.InputStream;
- import java.io.IOException;
- /**
- * A partial implementation of the <code>ImageDecoder</code> interface
- * useful for subclassing.
- *
- * <p><b> This class is not a committed part of the JAI API. It may
- * be removed or changed in future releases of JAI.</b>
- */
- public abstract class ImageDecoderImpl implements ImageDecoder {
- /**
- * The <code>SeekableStream</code> associcted with this
- * <code>ImageEncoder</code>.
- */
- protected SeekableStream input;
- /**
- * The <code>ImageDecodeParam</code> object associated with this
- * <code>ImageEncoder</code>.
- */
- protected ImageDecodeParam param;
- /**
- * Constructs an <code>ImageDecoderImpl</code> with a given
- * <code>SeekableStream</code> and <code>ImageDecodeParam</code>
- * instance.
- */
- public ImageDecoderImpl(SeekableStream input,
- ImageDecodeParam param) {
- this.input = input;
- this.param = param;
- }
- /**
- * Constructs an <code>ImageDecoderImpl</code> with a given
- * <code>InputStream</code> and <code>ImageDecodeParam</code>
- * instance. The <code>input</code> parameter will be used to
- * construct a <code>ForwardSeekableStream</code>; if the ability
- * to seek backwards is required, the caller should construct
- * an instance of <code>SeekableStream</code> and
- * make use of the other contructor.
- */
- public ImageDecoderImpl(InputStream input,
- ImageDecodeParam param) {
- this.input = new ForwardSeekableStream(input);
- this.param = param;
- }
- /**
- * Returns the current parameters as an instance of the
- * <code>ImageDecodeParam</code> interface. Concrete
- * implementations of this interface will return corresponding
- * concrete implementations of the <code>ImageDecodeParam</code>
- * interface. For example, a <code>JPEGImageDecoder</code> will
- * return an instance of <code>JPEGDecodeParam</code>.
- */
- public ImageDecodeParam getParam() {
- return param;
- }
- /**
- * Sets the current parameters to an instance of the
- * <code>ImageDecodeParam</code> interface. Concrete
- * implementations of <code>ImageDecoder</code> may throw a
- * <code>RuntimeException</code> if the <code>param</code>
- * argument is not an instance of the appropriate subclass or
- * subinterface. For example, a <code>JPEGImageDecoder</code>
- * will expect <code>param</code> to be an instance of
- * <code>JPEGDecodeParam</code>.
- */
- public void setParam(ImageDecodeParam param) {
- this.param = param;
- }
- /**
- * Returns the <code>SeekableStream</code> associated with
- * this <code>ImageDecoder</code>.
- */
- public SeekableStream getInputStream() {
- return input;
- }
- /**
- * Returns the number of pages present in the current stream.
- * By default, the return value is 1. Subclasses that deal with
- * multi-page formats should override this method.
- */
- public int getNumPages() throws IOException {
- return 1;
- }
-
- /**
- * Returns a <code>Raster</code> that contains the decoded
- * contents of the <code>SeekableStream</code> associated
- * with this <code>ImageDecoder</code>. Only
- * the first page of a multi-page image is decoded.
- */
- public Raster decodeAsRaster() throws IOException {
- return decodeAsRaster(0);
- }
- /**
- * Returns a <code>Raster</code> that contains the decoded
- * contents of the <code>SeekableStream</code> associated
- * with this <code>ImageDecoder</code>.
- * The given page of a multi-page image is decoded. If
- * the page does not exist, an IOException will be thrown.
- * Page numbering begins at zero.
- *
- * @param page The page to be decoded.
- */
- public Raster decodeAsRaster(int page) throws IOException {
- RenderedImage im = decodeAsRenderedImage(page);
- return im.getData();
- }
- /**
- * Returns a <code>RenderedImage</code> that contains the decoded
- * contents of the <code>SeekableStream</code> associated
- * with this <code>ImageDecoder</code>. Only
- * the first page of a multi-page image is decoded.
- */
- public RenderedImage decodeAsRenderedImage() throws IOException {
- return decodeAsRenderedImage(0);
- }
- /**
- * Returns a <code>RenderedImage</code> that contains the decoded
- * contents of the <code>SeekableStream</code> associated
- * with this <code>ImageDecoder</code>.
- * The given page of a multi-page image is decoded. If
- * the page does not exist, an IOException will be thrown.
- * Page numbering begins at zero.
- *
- * @param page The page to be decoded.
- */
- public abstract RenderedImage decodeAsRenderedImage(int page)
- throws IOException;
- }