imageio.java

linux下建立JAVA虚拟机的源码KAFFE

/* ImageIO.java --
   Copyright (C) 2004, 2005  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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 for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */


package javax.imageio;

import java.awt.image.BufferedImage;
import java.awt.image.RenderedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;

import javax.imageio.spi.IIORegistry;
import javax.imageio.spi.ImageInputStreamSpi;
import javax.imageio.spi.ImageOutputStreamSpi;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.spi.ImageTranscoderSpi;
import javax.imageio.spi.ImageWriterSpi;
import javax.imageio.spi.ServiceRegistry;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.stream.ImageOutputStream;
import javax.imageio.stream.MemoryCacheImageInputStream;
import javax.imageio.stream.MemoryCacheImageOutputStream;

/**
 * An uninstantiable class that provides static methods for locating
 * and using image readers and writers.
 */
public final class ImageIO
{
  /**
   * Construct an ImageIO.  Private since ImageIO is not instantiable.
   */
  private ImageIO()
  {
  }

  private static final class ReaderFormatFilter implements ServiceRegistry.Filter
  {
    private String formatName;

    public ReaderFormatFilter(String formatName)
    {
      this.formatName = formatName;
    }

    public boolean filter (Object provider)
    {
      if (provider instanceof ImageReaderSpi)
        {
          ImageReaderSpi spi = (ImageReaderSpi) provider;
          String[] formatNames = spi.getFormatNames();

          for (int i = formatNames.length - 1; i >= 0; --i)
            if (formatName.equals(formatNames[i]))
              return true;
        }

      return false;
    }
  }

  private static final class ReaderMIMETypeFilter implements ServiceRegistry.Filter
  {
    private String MIMEType;

    public ReaderMIMETypeFilter(String MIMEType)
    {
      this.MIMEType = MIMEType;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageReaderSpi)
        {
          ImageReaderSpi spi = (ImageReaderSpi) provider;
          String[] mimetypes = spi.getMIMETypes();

          for (int i = mimetypes.length - 1; i >= 0; --i)
            if (MIMEType.equals(mimetypes[i]))
              return true;
        }

      return false;
    }
  }
  
  private static final class ReaderObjectFilter implements ServiceRegistry.Filter
  {
    private Object object;

    public ReaderObjectFilter(Object object)
    {
      this.object = object;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageReaderSpi)
        {
          ImageReaderSpi spi = (ImageReaderSpi) provider;

          try
            {
              if (spi.canDecodeInput(object))
                return true;
            }
          catch (IOException e)
            {
              // Return false in this case
            }
        }
      return false;
    }
  }

  private static final class ReaderSuffixFilter implements ServiceRegistry.Filter
  {
    private String fileSuffix;

    public ReaderSuffixFilter(String fileSuffix)
    {
      this.fileSuffix = fileSuffix;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageReaderSpi)
        {
          ImageReaderSpi spi = (ImageReaderSpi) provider;
          String[] suffixes = spi.getFileSuffixes();

          for (int i = suffixes.length - 1; i >= 0; --i)
            if (fileSuffix.equals(suffixes[i]))
              return true;
        }

      return false;
    }
  }
  
  private static final class WriterFormatFilter implements ServiceRegistry.Filter
  {
    private String formatName;

    public WriterFormatFilter(String formatName)
    {
      this.formatName = formatName;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageWriterSpi)
	{
	  ImageWriterSpi spi = (ImageWriterSpi) provider;
	  String[] formatNames = spi.getFormatNames();
	  
	  for (int i = formatNames.length - 1; i >= 0; --i)
            if (formatName.equals(formatNames[i]))
              return true;
	}

      return false;
    }
  }

  private static final class WriterMIMETypeFilter implements ServiceRegistry.Filter
  {
    private String MIMEType;

    public WriterMIMETypeFilter(String MIMEType)
    {
      this.MIMEType = MIMEType;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageWriterSpi)
        {
          ImageWriterSpi spi = (ImageWriterSpi) provider;
          String[] mimetypes = spi.getMIMETypes();

          for (int i = mimetypes.length - 1; i >= 0; --i)
            if (MIMEType.equals(mimetypes[i]))
              return true;
        }

      return false;
    }
  }
  
  private static final class WriterSuffixFilter implements ServiceRegistry.Filter
  {
    private String fileSuffix;

    public WriterSuffixFilter(String fileSuffix)
    {
      this.fileSuffix = fileSuffix;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageWriterSpi)
        {
          ImageWriterSpi spi = (ImageWriterSpi) provider;
          String[] suffixes = spi.getFileSuffixes();

          for (int i = suffixes.length - 1; i >= 0; --i)
            if (fileSuffix.equals(suffixes[i]))
              return true;
        }

      return false;
    }
  }

  private static final class WriterObjectFilter implements ServiceRegistry.Filter
  {
    private ImageTypeSpecifier type;
    private String formatName;

    public WriterObjectFilter(ImageTypeSpecifier type,
			      String formatName)
    {
      this.type = type;
      this.formatName = formatName;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageWriterSpi)
        {
          ImageWriterSpi spi = (ImageWriterSpi) provider;

	  if (spi.canEncodeImage(type))
	    {
	      String[] formatNames = spi.getFormatNames();
	      for (int i = formatNames.length - 1; i >= 0; --i)
		if (formatName.equals(formatNames[i]))
		  return true;
	    }
        }

      return false;
    }
  }

  private static final class TranscoderFilter implements ServiceRegistry.Filter
  {
    private ImageReader reader;
    private ImageWriter writer;

    public TranscoderFilter(ImageReader reader,
                            ImageWriter writer)
    {
      this.reader = reader;
      this.writer = writer;
    }

    public boolean filter(Object provider)
    {
      if (provider instanceof ImageTranscoderSpi)
        {
          ImageTranscoderSpi spi = (ImageTranscoderSpi) provider;

	  if (spi.getReaderServiceProviderName().equals
	      (reader.getOriginatingProvider().getClass().getName())
	      && spi.getWriterServiceProviderName().equals
	      (writer.getOriginatingProvider().getClass().getName()))
	    return true;
        }

      return false;
    }
  }

  private static final class ImageReaderIterator implements Iterator
  {
    Iterator it;
    Object readerExtension;
    
    public ImageReaderIterator(Iterator it, Object readerExtension)
    {
      this.it = it;
      this.readerExtension = readerExtension;
    }

    public boolean hasNext()
    {
      return it.hasNext();
    }

    public Object next()
    {
      try
        {
          return ((ImageReaderSpi) it.next()).createReaderInstance(readerExtension);
        }
      catch (IOException e)
        {
          return null;
        }
    }

    public void remove()
    {
      throw new UnsupportedOperationException();
    }
  }

  private static final class ImageWriterIterator implements Iterator
  {
    Iterator it;
    Object writerExtension;
    
    public ImageWriterIterator(Iterator it, Object writerExtension)
    {
      this.it = it;
      this.writerExtension = writerExtension;
    }

    public boolean hasNext()
    {
      return it.hasNext();
    }

    public Object next()
    {
      try
        {
          return ((ImageWriterSpi) it.next()).createWriterInstance(writerExtension);
        }
      catch (IOException e)
        {
          return null;
        }
    }

    public void remove()
    {
      throw new UnsupportedOperationException();
    }
  }
  
  private static File cacheDirectory;
  private static boolean useCache = true;

  private static Iterator getReadersByFilter(Class type,
                                             ServiceRegistry.Filter filter,
                                             Object readerExtension)
  {
    try
      {
        Iterator it = getRegistry().getServiceProviders(type, filter, true);
        return new ImageReaderIterator(it, readerExtension);
      }
    catch (IllegalArgumentException e)
      {
        return Collections.EMPTY_SET.iterator();