ImageIOExportFileType.java

// Copyright 2003-2014 FreeHEP
package org.freehep.graphicsio.exportchooser;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;

import javax.imageio.ImageIO;
import javax.imageio.ImageWriter;
import javax.imageio.spi.IIORegistry;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.spi.ImageWriterSpi;
import javax.imageio.spi.RegisterableService;
import javax.imageio.spi.ServiceRegistry;

import org.freehep.graphicsbase.util.export.ExportFileType;
import org.freehep.graphicsbase.util.export.ExportFileTypeRegistry;
import org.freehep.graphicsio.ImageGraphics2D;

/**
 * This class does not work, since the ExportFileTypeRegistry stores Objects by
 * class. If we automatically generate ImageFileTypes by ImageIO they end up
 * being all different objects from the same class. The Registry currently then
 * overwrites the first one with the second and so on. Sun Bug #Submitted.
 * 
 * @author Mark Donszelmann
 */
public class ImageIOExportFileType implements RegisterableService {

	private List<ImageWriterSpi> providerList = new ArrayList<ImageWriterSpi>();
	
    /**
     * This constructor will construct register all image formats available in
     * ImageIO into ExportFileTypeRegistry. The ImageExportFileTypeRegistration
     * will deregister itself immediately.
     */
    public ImageIOExportFileType() {
        // NOTE: registry is not valid yet, imageRegistry is valid

    	// run over all ImageWriterSpis and store their formats Alphabetically
    	// copy them at this time to avoid a ConcurrentModificationException
    	// see https://github.com/freehep/freehep-vectorgraphics/issues/23
        IIORegistry imageRegistry = IIORegistry.getDefaultInstance();
        Iterator<?> providers = imageRegistry.getServiceProviders(
                ImageWriterSpi.class, false);
        while (providers.hasNext()) {
            ImageWriterSpi writerSpi = (ImageWriterSpi) providers.next();
            providerList.add(writerSpi);
        }
    }

    @SuppressWarnings("unchecked")
	public void onRegistration(ServiceRegistry registry, Class<?> category) {
        // run over all ImageWriterSpis and store their formats Alphabetically
        Iterator<ImageWriterSpi> providers = providerList.iterator();
    	ExportFileTypeRegistry exportRegistry = ExportFileTypeRegistry.getDefaultInstance(null);
        while (providers.hasNext()) {
            ImageWriterSpi writerSpi = (ImageWriterSpi) providers.next();
        	String[] formats = writerSpi.getFileSuffixes();
            if ((formats != null) && (formats[0] != null)) {
            	exportRegistry.add(new ImageExportFileType(writerSpi));
            } else {
                System.err.println(getClass() + ": Cannot register "
                        + writerSpi + " because it has no filesuffixes.");
            }
        }    
        
        registry.deregisterServiceProvider(this, (Class<ImageIOExportFileType>)category);
    }

    public void onDeregistration(ServiceRegistry registry, Class<?> category) {
    }

    public static void main(String[] args) throws Exception {

        System.out.println("WRITERS");
        IIORegistry imageRegistry = IIORegistry.getDefaultInstance();
        Iterator<?> providers = imageRegistry.getServiceProviders(
                ImageWriterSpi.class, false);
        while (providers.hasNext()) {
            ImageWriterSpi writerSpi = (ImageWriterSpi) providers.next();
            System.out.println("   " + writerSpi);
            System.out.println("      " + writerSpi.getDescription(Locale.US));
            System.out.print("      ");
            String[] formats = writerSpi.getFileSuffixes();
            for (int i = 0; i < formats.length; i++) {
                System.out.print(formats[i] + ", ");
            }
            System.out.println();
        }
        System.out.println();

        System.out.println("MIMETYPES");
        String[] formats = ImageIO.getWriterMIMETypes();
        for (int i = 0; i < formats.length; i++) {
            System.out.println("   " + formats[i]);
            ImageWriter writer = ImageGraphics2D
                    .getPreferredImageWriterForMIMEType(formats[i]);
            String[] suffixes = writer.getOriginatingProvider()
                    .getFileSuffixes();
            System.out.print("      ");
            for (int j = 0; j < suffixes.length; j++) {
                System.out.print(suffixes[j] + " ");
            }
            System.out.println();
            System.out.println("      " + writer);
        }

        System.out.println();

        System.out.println("READERS");
        providers = imageRegistry.getServiceProviders(ImageReaderSpi.class,
                false);
        while (providers.hasNext()) {
            System.out.println("   " + providers.next());
        }
        System.out.println();

        System.out.println("All ExportFileTypes");
        List<?> exportFileTypes = ExportFileType.getExportFileTypes();
        Iterator<?> iterator = exportFileTypes.iterator();
        while (iterator.hasNext()) {
        	ExportFileType type = (ExportFileType)iterator.next();
            System.out.println("   " + type);
        }
    }
}