| /* |
| * Copyright (c) 1999, 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 javax.imageio.spi; |
| |
| import java.awt.image.RenderedImage; |
| import java.io.IOException; |
| import javax.imageio.ImageTypeSpecifier; |
| import javax.imageio.ImageWriter; |
| import javax.imageio.stream.ImageOutputStream; |
| |
| /** |
| * The service provider interface (SPI) for {@code ImageWriter}s. |
| * For more information on service provider classes, see the class comment |
| * for the {@code IIORegistry} class. |
| * |
| * <p> Each {@code ImageWriterSpi} provides several types of information |
| * about the {@code ImageWriter} class with which it is associated. |
| * |
| * <p> The name of the vendor who defined the SPI class and a |
| * brief description of the class are available via the |
| * {@code getVendorName}, {@code getDescription}, |
| * and {@code getVersion} methods. |
| * These methods may be internationalized to provide locale-specific |
| * output. These methods are intended mainly to provide short, |
| * human-writable information that might be used to organize a pop-up |
| * menu or other list. |
| * |
| * <p> Lists of format names, file suffixes, and MIME types associated |
| * with the service may be obtained by means of the |
| * {@code getFormatNames}, {@code getFileSuffixes}, and |
| * {@code getMIMEType} methods. These methods may be used to |
| * identify candidate {@code ImageWriter}s for writing a |
| * particular file or stream based on manual format selection, file |
| * naming, or MIME associations. |
| * |
| * <p> A more reliable way to determine which {@code ImageWriter}s |
| * are likely to be able to parse a particular data stream is provided |
| * by the {@code canEncodeImage} method. This methods allows the |
| * service provider to inspect the actual image contents. |
| * |
| * <p> Finally, an instance of the {@code ImageWriter} class |
| * associated with this service provider may be obtained by calling |
| * the {@code createWriterInstance} method. Any heavyweight |
| * initialization, such as the loading of native libraries or creation |
| * of large tables, should be deferred at least until the first |
| * invocation of this method. |
| * |
| * @see IIORegistry |
| * @see javax.imageio.ImageTypeSpecifier |
| * @see javax.imageio.ImageWriter |
| * |
| */ |
| public abstract class ImageWriterSpi extends ImageReaderWriterSpi { |
| |
| /** |
| * A single-element array, initially containing |
| * {@code ImageOutputStream.class}, to be returned from |
| * {@code getOutputTypes}. |
| * @deprecated Instead of using this field, directly create |
| * the equivalent array {@code { ImageOutputStream.class }}. |
| */ |
| @Deprecated |
| public static final Class<?>[] STANDARD_OUTPUT_TYPE = |
| { ImageOutputStream.class }; |
| |
| /** |
| * An array of {@code Class} objects to be returned from |
| * {@code getOutputTypes}, initially {@code null}. |
| */ |
| protected Class<?>[] outputTypes = null; |
| |
| /** |
| * An array of strings to be returned from |
| * {@code getImageReaderSpiNames}, initially |
| * {@code null}. |
| */ |
| protected String[] readerSpiNames = null; |
| |
| /** |
| * The {@code Class} of the writer, initially |
| * {@code null}. |
| */ |
| private Class<?> writerClass = null; |
| |
| /** |
| * Constructs a blank {@code ImageWriterSpi}. It is up to |
| * the subclass to initialize instance variables and/or override |
| * method implementations in order to provide working versions of |
| * all methods. |
| */ |
| protected ImageWriterSpi() { |
| } |
| |
| /** |
| * Constructs an {@code ImageWriterSpi} with a given |
| * set of values. |
| * |
| * @param vendorName the vendor name, as a non-{@code null} |
| * {@code String}. |
| * @param version a version identifier, as a non-{@code null} |
| * {@code String}. |
| * @param names a non-{@code null} array of |
| * {@code String}s indicating the format names. At least one |
| * entry must be present. |
| * @param suffixes an array of {@code String}s indicating the |
| * common file suffixes. If no suffixes are defined, |
| * {@code null} should be supplied. An array of length 0 |
| * will be normalized to {@code null}. |
| * @param MIMETypes an array of {@code String}s indicating |
| * the format's MIME types. If no suffixes are defined, |
| * {@code null} should be supplied. An array of length 0 |
| * will be normalized to {@code null}. |
| * @param writerClassName the fully-qualified name of the |
| * associated {@code ImageWriterSpi} class, as a |
| * non-{@code null String}. |
| * @param outputTypes an array of {@code Class} objects of |
| * length at least 1 indicating the legal output types. |
| * @param readerSpiNames an array {@code String}s of length |
| * at least 1 naming the classes of all associated |
| * {@code ImageReader}s, or {@code null}. An array of |
| * length 0 is normalized to {@code null}. |
| * @param supportsStandardStreamMetadataFormat a |
| * {@code boolean} that indicates whether a stream metadata |
| * object can use trees described by the standard metadata format. |
| * @param nativeStreamMetadataFormatName a |
| * {@code String}, or {@code null}, to be returned from |
| * {@code getNativeStreamMetadataFormatName}. |
| * @param nativeStreamMetadataFormatClassName a |
| * {@code String}, or {@code null}, to be used to instantiate |
| * a metadata format object to be returned from |
| * {@code getNativeStreamMetadataFormat}. |
| * @param extraStreamMetadataFormatNames an array of |
| * {@code String}s, or {@code null}, to be returned from |
| * {@code getExtraStreamMetadataFormatNames}. An array of length |
| * 0 is normalized to {@code null}. |
| * @param extraStreamMetadataFormatClassNames an array of |
| * {@code String}s, or {@code null}, to be used to instantiate |
| * a metadata format object to be returned from |
| * {@code getStreamMetadataFormat}. An array of length |
| * 0 is normalized to {@code null}. |
| * @param supportsStandardImageMetadataFormat a |
| * {@code boolean} that indicates whether an image metadata |
| * object can use trees described by the standard metadata format. |
| * @param nativeImageMetadataFormatName a |
| * {@code String}, or {@code null}, to be returned from |
| * {@code getNativeImageMetadataFormatName}. |
| * @param nativeImageMetadataFormatClassName a |
| * {@code String}, or {@code null}, to be used to instantiate |
| * a metadata format object to be returned from |
| * {@code getNativeImageMetadataFormat}. |
| * @param extraImageMetadataFormatNames an array of |
| * {@code String}s to be returned from |
| * {@code getExtraImageMetadataFormatNames}. An array of length 0 |
| * is normalized to {@code null}. |
| * @param extraImageMetadataFormatClassNames an array of |
| * {@code String}s, or {@code null}, to be used to instantiate |
| * a metadata format object to be returned from |
| * {@code getImageMetadataFormat}. An array of length |
| * 0 is normalized to {@code null}. |
| * |
| * @exception IllegalArgumentException if {@code vendorName} |
| * is {@code null}. |
| * @exception IllegalArgumentException if {@code version} |
| * is {@code null}. |
| * @exception IllegalArgumentException if {@code names} |
| * is {@code null} or has length 0. |
| * @exception IllegalArgumentException if {@code writerClassName} |
| * is {@code null}. |
| * @exception IllegalArgumentException if {@code outputTypes} |
| * is {@code null} or has length 0. |
| */ |
| public ImageWriterSpi(String vendorName, |
| String version, |
| String[] names, |
| String[] suffixes, |
| String[] MIMETypes, |
| String writerClassName, |
| Class<?>[] outputTypes, |
| String[] readerSpiNames, |
| boolean supportsStandardStreamMetadataFormat, |
| String nativeStreamMetadataFormatName, |
| String nativeStreamMetadataFormatClassName, |
| String[] extraStreamMetadataFormatNames, |
| String[] extraStreamMetadataFormatClassNames, |
| boolean supportsStandardImageMetadataFormat, |
| String nativeImageMetadataFormatName, |
| String nativeImageMetadataFormatClassName, |
| String[] extraImageMetadataFormatNames, |
| String[] extraImageMetadataFormatClassNames) { |
| super(vendorName, version, |
| names, suffixes, MIMETypes, writerClassName, |
| supportsStandardStreamMetadataFormat, |
| nativeStreamMetadataFormatName, |
| nativeStreamMetadataFormatClassName, |
| extraStreamMetadataFormatNames, |
| extraStreamMetadataFormatClassNames, |
| supportsStandardImageMetadataFormat, |
| nativeImageMetadataFormatName, |
| nativeImageMetadataFormatClassName, |
| extraImageMetadataFormatNames, |
| extraImageMetadataFormatClassNames); |
| |
| if (outputTypes == null) { |
| throw new IllegalArgumentException |
| ("outputTypes == null!"); |
| } |
| if (outputTypes.length == 0) { |
| throw new IllegalArgumentException |
| ("outputTypes.length == 0!"); |
| } |
| |
| this.outputTypes = (outputTypes == STANDARD_OUTPUT_TYPE) ? |
| new Class<?>[] { ImageOutputStream.class } : |
| outputTypes.clone(); |
| |
| // If length == 0, leave it null |
| if (readerSpiNames != null && readerSpiNames.length > 0) { |
| this.readerSpiNames = readerSpiNames.clone(); |
| } |
| } |
| |
| /** |
| * Returns {@code true} if the format that this writer |
| * outputs preserves pixel data bit-accurately. The default |
| * implementation returns {@code true}. |
| * |
| * @return {@code true} if the format preserves full pixel |
| * accuracy. |
| */ |
| public boolean isFormatLossless() { |
| return true; |
| } |
| |
| /** |
| * Returns an array of {@code Class} objects indicating what |
| * types of objects may be used as arguments to the writer's |
| * {@code setOutput} method. |
| * |
| * <p> For most writers, which only output to an |
| * {@code ImageOutputStream}, a single-element array |
| * containing {@code ImageOutputStream.class} should be |
| * returned. |
| * |
| * @return a non-{@code null} array of |
| * {@code Class} objects of length at least 1. |
| */ |
| public Class<?>[] getOutputTypes() { |
| return outputTypes.clone(); |
| } |
| |
| /** |
| * Returns {@code true} if the {@code ImageWriter} |
| * implementation associated with this service provider is able to |
| * encode an image with the given layout. The layout |
| * (<i>i.e.</i>, the image's {@code SampleModel} and |
| * {@code ColorModel}) is described by an |
| * {@code ImageTypeSpecifier} object. |
| * |
| * <p> A return value of {@code true} is not an absolute |
| * guarantee of successful encoding; the encoding process may still |
| * produce errors due to factors such as I/O errors, inconsistent |
| * or malformed data structures, etc. The intent is that a |
| * reasonable inspection of the basic structure of the image be |
| * performed in order to determine if it is within the scope of |
| * the encoding format. For example, a service provider for a |
| * format that can only encode greyscale would return |
| * {@code false} if handed an RGB {@code BufferedImage}. |
| * Similarly, a service provider for a format that can encode |
| * 8-bit RGB imagery might refuse to encode an image with an |
| * associated alpha channel. |
| * |
| * <p> Different {@code ImageWriter}s, and thus service |
| * providers, may choose to be more or less strict. For example, |
| * they might accept an image with premultiplied alpha even though |
| * it will have to be divided out of each pixel, at some loss of |
| * precision, in order to be stored. |
| * |
| * @param type an {@code ImageTypeSpecifier} specifying the |
| * layout of the image to be written. |
| * |
| * @return {@code true} if this writer is likely to be able |
| * to encode images with the given layout. |
| * |
| * @exception IllegalArgumentException if {@code type} |
| * is {@code null}. |
| */ |
| public abstract boolean canEncodeImage(ImageTypeSpecifier type); |
| |
| /** |
| * Returns {@code true} if the {@code ImageWriter} |
| * implementation associated with this service provider is able to |
| * encode the given {@code RenderedImage} instance. Note |
| * that this includes instances of |
| * {@code java.awt.image.BufferedImage}. |
| * |
| * <p> See the discussion for |
| * {@code canEncodeImage(ImageTypeSpecifier)} for information |
| * on the semantics of this method. |
| * |
| * @param im an instance of {@code RenderedImage} to be encoded. |
| * |
| * @return {@code true} if this writer is likely to be able |
| * to encode this image. |
| * |
| * @exception IllegalArgumentException if {@code im} |
| * is {@code null}. |
| */ |
| public boolean canEncodeImage(RenderedImage im) { |
| return canEncodeImage(ImageTypeSpecifier.createFromRenderedImage(im)); |
| } |
| |
| /** |
| * Returns an instance of the {@code ImageWriter} |
| * implementation associated with this service provider. |
| * The returned object will initially be in an initial state as if |
| * its {@code reset} method had been called. |
| * |
| * <p> The default implementation simply returns |
| * {@code createWriterInstance(null)}. |
| * |
| * @return an {@code ImageWriter} instance. |
| * |
| * @exception IOException if an error occurs during loading, |
| * or initialization of the writer class, or during instantiation |
| * or initialization of the writer object. |
| */ |
| public ImageWriter createWriterInstance() throws IOException { |
| return createWriterInstance(null); |
| } |
| |
| /** |
| * Returns an instance of the {@code ImageWriter} |
| * implementation associated with this service provider. |
| * The returned object will initially be in an initial state |
| * as if its {@code reset} method had been called. |
| * |
| * <p> An {@code Object} may be supplied to the plug-in at |
| * construction time. The nature of the object is entirely |
| * plug-in specific. |
| * |
| * <p> Typically, a plug-in will implement this method using code |
| * such as {@code return new MyImageWriter(this)}. |
| * |
| * @param extension a plug-in specific extension object, which may |
| * be {@code null}. |
| * |
| * @return an {@code ImageWriter} instance. |
| * |
| * @exception IOException if the attempt to instantiate |
| * the writer fails. |
| * @exception IllegalArgumentException if the |
| * {@code ImageWriter}'s constructor throws an |
| * {@code IllegalArgumentException} to indicate that the |
| * extension object is unsuitable. |
| */ |
| public abstract ImageWriter createWriterInstance(Object extension) |
| throws IOException; |
| |
| /** |
| * Returns {@code true} if the {@code ImageWriter} object |
| * passed in is an instance of the {@code ImageWriter} |
| * associated with this service provider. |
| * |
| * @param writer an {@code ImageWriter} instance. |
| * |
| * @return {@code true} if {@code writer} is recognized |
| * |
| * @exception IllegalArgumentException if {@code writer} is |
| * {@code null}. |
| */ |
| public boolean isOwnWriter(ImageWriter writer) { |
| if (writer == null) { |
| throw new IllegalArgumentException("writer == null!"); |
| } |
| String name = writer.getClass().getName(); |
| return name.equals(pluginClassName); |
| } |
| |
| /** |
| * Returns an array of {@code String}s containing all the |
| * fully qualified names of all the {@code ImageReaderSpi} |
| * classes that can understand the internal metadata |
| * representation used by the {@code ImageWriter} associated |
| * with this service provider, or {@code null} if there are |
| * no such {@code ImageReaders} specified. If a |
| * non-{@code null} value is returned, it must have non-zero |
| * length. |
| * |
| * <p> The first item in the array must be the name of the service |
| * provider for the "preferred" reader, as it will be used to |
| * instantiate the {@code ImageReader} returned by |
| * {@code ImageIO.getImageReader(ImageWriter)}. |
| * |
| * <p> This mechanism may be used to obtain |
| * {@code ImageReaders} that will generated non-pixel |
| * meta-data (see {@code IIOExtraDataInfo}) in a structure |
| * understood by an {@code ImageWriter}. By reading the |
| * image and obtaining this data from one of the |
| * {@code ImageReaders} obtained with this method and passing |
| * it on to the {@code ImageWriter}, a client program can |
| * read an image, modify it in some way, and write it back out |
| * preserving all meta-data, without having to understand anything |
| * about the internal structure of the meta-data, or even about |
| * the image format. |
| * |
| * @return an array of {@code String}s of length at least 1 |
| * containing names of {@code ImageReaderSpi}s, or |
| * {@code null}. |
| * |
| * @see javax.imageio.ImageIO#getImageReader(ImageWriter) |
| * @see ImageReaderSpi#getImageWriterSpiNames() |
| */ |
| public String[] getImageReaderSpiNames() { |
| return readerSpiNames == null ? |
| null : readerSpiNames.clone(); |
| } |
| } |