awt/javax/imageio/spi/ImageWriterSpi.java

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
/**
 * @author Rustem V. Rafikov
 * @version $Revision: 1.3 $
 */
package javax.imageio.spi;

import javax.imageio.stream.ImageInputStream;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.ImageWriter;
import java.awt.image.RenderedImage;
import java.io.IOException;

/**
 * The ImageWriterSpi abstract class is a service provider 
 * interface (SPI) for ImageWriters.
 */
public abstract class ImageWriterSpi extends ImageReaderWriterSpi {

    /** The STANDARD_OUTPUT_TYPE contains ImageInputStream.class. */
    public static final Class[] STANDARD_OUTPUT_TYPE = new Class[] {ImageInputStream.class};

    /** The output types. */
    protected Class[] outputTypes;
    
    /** The reader spi names. */
    protected String[] readerSpiNames;

    /**
     * Instantiates a new ImageWriterSpi.
     */
    protected ImageWriterSpi() {
        throw new UnsupportedOperationException("Not supported yet");
    }

    /**
     * Instantiates a new ImageWriterSpi with the specified parameters.
     * 
     * @param vendorName the vendor name.
     * @param version the version.
     * @param names the format names.
     * @param suffixes the array of strings representing the file suffixes. 
     * @param MIMETypes the an array of strings representing MIME types.
     * @param pluginClassName the plugin class name.
     * @param outputTypes the output types.
     * @param readerSpiNames the array of strings with class names of all 
     * associated ImageReaders.
     * @param supportsStandardStreamMetadataFormat the value indicating
     * if stream metadata can be described by standard metadata format.
     * @param nativeStreamMetadataFormatName the native stream metadata 
     * format name, returned by getNativeStreamMetadataFormatName.
     * @param nativeStreamMetadataFormatClassName the native stream 
     * metadata format class name, returned by getNativeStreamMetadataFormat.
     * @param extraStreamMetadataFormatNames the extra stream metadata 
     * format names, returned by getExtraStreamMetadataFormatNames.
     * @param extraStreamMetadataFormatClassNames the extra stream metadata 
     * format class names, returned by getStreamMetadataFormat.
     * @param supportsStandardImageMetadataFormat the value indicating
     * if image metadata can be described by standard metadata format.
     * @param nativeImageMetadataFormatName the native image metadata 
     * format name, returned by getNativeImageMetadataFormatName.
     * @param nativeImageMetadataFormatClassName the native image
     * metadata format class name, returned by getNativeImageMetadataFormat.
     * @param extraImageMetadataFormatNames the extra image metadata 
     * format names, returned by getExtraImageMetadataFormatNames.
     * @param extraImageMetadataFormatClassNames the extra image metadata 
     * format class names, returned by getImageMetadataFormat.
     */
    public ImageWriterSpi(String vendorName, String version, String[] names,
                             String[] suffixes, String[] MIMETypes,
                             String pluginClassName,
                             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, pluginClassName,
                supportsStandardStreamMetadataFormat, nativeStreamMetadataFormatName,
                nativeStreamMetadataFormatClassName, extraStreamMetadataFormatNames,
                extraStreamMetadataFormatClassNames, supportsStandardImageMetadataFormat,
                nativeImageMetadataFormatName, nativeImageMetadataFormatClassName,
                extraImageMetadataFormatNames, extraImageMetadataFormatClassNames);

        if (outputTypes == null || outputTypes.length == 0) {
            throw new NullPointerException("output types array cannot be NULL or empty");
        }

        this.outputTypes = outputTypes;
        this.readerSpiNames = readerSpiNames;
    }

    /**
     * Returns true if the format of the writer's output is lossless. 
     * The default implementation returns true.
     * 
     * @return true, if a format is lossless, false otherwise.
     */
    public boolean isFormatLossless() {
        return true;
    }

    /**
     * Gets an array of Class objects whose types 
     * can be used as output for this writer.
     * 
     * @return the output types.
     */
    public Class[] getOutputTypes() {
        return outputTypes;
    }

    /**
     * Checks whether or not the ImageWriter implementation associated 
     * with this service provider can encode an image with 
     * the specified type.
     * 
     * @param type the ImageTypeSpecifier.
     * 
     * @return true, if an image with the specified type can be
     * encoded, false otherwise. 
     */
    public abstract boolean canEncodeImage(ImageTypeSpecifier type);

    /**
     * Checks whether or not the ImageWriter implementation associated 
     * with this service provider can encode the specified RenderedImage.
     * 
     * @param im the RenderedImage.
     * 
     * @return true, if RenderedImage can be encoded, 
     * false otherwise. 
     */
    public boolean canEncodeImage(RenderedImage im) {
        return canEncodeImage(ImageTypeSpecifier.createFromRenderedImage(im));
    }

    /**
     * Returns an instance of the ImageWriter implementation for
     * this service provider.
     * 
     * @return the ImageWriter.
     * 
     * @throws IOException Signals that an I/O exception has occurred.
     */
    public ImageWriter createWriterInstance() throws IOException {
        return createWriterInstance(null);
    }

    /**
     * Returns an instance of the ImageWriter implementation for
     * this service provider.
     * 
     * @param extension the a plugin specific extension object, or null.
     * 
     * @return the ImageWriter.
     * 
     * @throws IOException Signals that an I/O exception has occurred.
     */
    public abstract ImageWriter createWriterInstance(Object extension) throws IOException;

    /**
     * Checks whether or not the specified ImageWriter object 
     * is an instance of the ImageWriter associated with this 
     * service provider or not.
     * 
     * @param writer the ImageWriter.
     * 
     * @return true, if the specified ImageWriter object 
     * is an instance of the ImageWriter associated with this 
     * service provider, false otherwise.
     */
    public boolean isOwnWriter(ImageWriter writer) {
        throw new UnsupportedOperationException("Not supported yet");
    }

    /**
     * Gets an array of strings with names of the ImageReaderSpi 
     * classes that support the internal metadata representation 
     * used by the ImageWriter of this service provider, or null if 
     * there are no such ImageReaders.
     * 
     * @return an array of strings with names of the ImageWriterSpi 
     * classes.
     */
    public String[] getImageReaderSpiNames() {
        return readerSpiNames;
    }
}