GIFImageReaderSpi.java 4.5 KB

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  1. /* GIFImageReaderSpi.java --
  2. Copyright (C) 2006 Free Software Foundation, Inc.
  3. This file is part of GNU Classpath.
  4. GNU Classpath is free software; you can redistribute it and/or modify
  5. it under the terms of the GNU General Public License as published by
  6. the Free Software Foundation; either version 2, or (at your option)
  7. any later version.
  8. GNU Classpath is distributed in the hope that it will be useful, but
  9. WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. General Public License for more details.
  12. You should have received a copy of the GNU General Public License
  13. along with GNU Classpath; see the file COPYING. If not, write to the
  14. Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  15. 02110-1301 USA.
  16. Linking this library statically or dynamically with other modules is
  17. making a combined work based on this library. Thus, the terms and
  18. conditions of the GNU General Public License cover the whole
  19. combination.
  20. As a special exception, the copyright holders of this library give you
  21. permission to link this library with independent modules to produce an
  22. executable, regardless of the license terms of these independent
  23. modules, and to copy and distribute the resulting executable under
  24. terms of your choice, provided that you also meet, for each linked
  25. independent module, the terms and conditions of the license of that
  26. module. An independent module is a module which is not derived from
  27. or based on this library. If you modify this library, you may extend
  28. this exception to your version of the library, but you are not
  29. obligated to do so. If you do not wish to do so, delete this
  30. exception statement from your version. */
  31. package gnu.javax.imageio.gif;
  32. import gnu.javax.imageio.IIOInputStream;
  33. import java.io.InputStream;
  34. import java.io.IOException;
  35. import java.util.Locale;
  36. import javax.imageio.ImageReader;
  37. import javax.imageio.spi.ImageReaderSpi;
  38. import javax.imageio.stream.ImageInputStream;
  39. public class GIFImageReaderSpi extends ImageReaderSpi
  40. {
  41. static final String vendorName = "GNU";
  42. static final String version = "0.1";
  43. static final String readerClassName =
  44. "gnu.javax.imageio.gif.GIFImageReader";
  45. static final String[] names = { "Compuserve GIF" };
  46. static final String[] suffixes = { ".gif" };
  47. static final String[] MIMETypes = {
  48. "image/gif",
  49. "image/x-gif"}; // Not sure this is legal, but it seems to be used a bit
  50. static final String[] writerSpiNames = null;
  51. static final boolean supportsStandardStreamMetadataFormat = false;
  52. static final String nativeStreamMetadataFormatName = null;
  53. static final String nativeStreamMetadataFormatClassName = null;
  54. static final String[] extraStreamMetadataFormatNames = null;
  55. static final String[] extraStreamMetadataFormatClassNames = null;
  56. static final boolean supportsStandardImageMetadataFormat = false;
  57. static final String nativeImageMetadataFormatName = null;
  58. static final String nativeImageMetadataFormatClassName = null;
  59. static final String[] extraImageMetadataFormatNames = null;
  60. static final String[] extraImageMetadataFormatClassNames = null;
  61. public GIFImageReaderSpi()
  62. {
  63. super(vendorName, version,
  64. names, suffixes, MIMETypes,
  65. readerClassName,
  66. new Class[]{ ImageInputStream.class, InputStream.class },
  67. writerSpiNames,
  68. supportsStandardStreamMetadataFormat,
  69. nativeStreamMetadataFormatName,
  70. nativeStreamMetadataFormatClassName,
  71. extraStreamMetadataFormatNames,
  72. extraStreamMetadataFormatClassNames,
  73. supportsStandardImageMetadataFormat,
  74. nativeImageMetadataFormatName,
  75. nativeImageMetadataFormatClassName,
  76. extraImageMetadataFormatNames,
  77. extraImageMetadataFormatClassNames);
  78. }
  79. public String getDescription(Locale locale)
  80. {
  81. return "Compuserve GIF";
  82. }
  83. public boolean canDecodeInput(Object input)
  84. throws IOException
  85. {
  86. if( input == null )
  87. throw new IllegalArgumentException("Input object cannot be null.");
  88. if( !(input instanceof ImageInputStream) &&
  89. !(input instanceof InputStream))
  90. return false;
  91. boolean retval;
  92. InputStream in;
  93. if( input instanceof ImageInputStream )
  94. in = new IIOInputStream( (ImageInputStream)input );
  95. else
  96. in = (InputStream)input;
  97. in.mark(10); // we read 6 bytes
  98. retval = GIFFile.readSignature( in );
  99. in.reset();
  100. return retval;
  101. }
  102. public ImageReader createReaderInstance(Object extension)
  103. {
  104. return new GIFImageReader(this);
  105. }
  106. }