libjava/classpath/gnu/javax/imageio/bmp/BMPImageReader.java

   1 /* BMPImageReader.java --
   2    Copyright (C)  2005  Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38 package gnu.javax.imageio.bmp;
  39
  40 import java.io.IOException;
  41 import javax.imageio.*;
  42 import javax.imageio.spi.*;
  43 import javax.imageio.metadata.*;
  44 import javax.imageio.stream.ImageInputStream;
  45 import java.util.Iterator;
  46 import java.awt.image.BufferedImage;
  47
  48 public class BMPImageReader extends ImageReader {
  49     private BMPInfoHeader infoHeader;
  50     private BMPFileHeader fileHeader;
  51     private BMPDecoder decoder;
  52
  53     protected BMPImageReader(ImageReaderSpi originatingProvider){
  54         super(originatingProvider);
  55         infoHeader = null;
  56         fileHeader = null;
  57         decoder = null;
  58     }
  59
  60     private void validateIndex(int imageIndex)
  61         throws IndexOutOfBoundsException {
  62         if (imageIndex != 0)
  63             throw new IndexOutOfBoundsException("Invalid image index.");
  64     }
  65
  66     public void setInput(Object input) {
  67         super.setInput(input);
  68     }
  69
  70     public void setInput(Object input,
  71                          boolean seekForwardOnly,
  72                          boolean ignoreMetadata) {
  73         super.setInput(input, seekForwardOnly, ignoreMetadata);
  74     }
  75
  76     public void setInput(Object input, boolean isStreamable) {
  77         super.setInput(input, isStreamable);
  78
  79         if (!(input instanceof ImageInputStream))
  80             throw new IllegalArgumentException("Input not an ImageInputStream.");
  81     }
  82
  83     private void checkStream() throws IOException {
  84         if (!(input instanceof ImageInputStream))
  85             throw new IllegalStateException("Input not an ImageInputStream.");
  86         if(input == null)
  87             throw new IllegalStateException("No input stream.");
  88
  89     }
  90
  91     private void readHeaders() throws IOException, IIOException {
  92         if(fileHeader != null)
  93             return;
  94
  95         checkStream();
  96
  97         fileHeader = new BMPFileHeader((ImageInputStream)input);
  98         infoHeader = new BMPInfoHeader((ImageInputStream)input);
  99         decoder = BMPDecoder.getDecoder(fileHeader, infoHeader);
 100     }
 101
 102     public int getWidth(int imageIndex) throws IOException {
 103         validateIndex(imageIndex);
 104         readHeaders();
 105         return infoHeader.getWidth();
 106     }
 107
 108     public int getHeight(int imageIndex) throws IOException {
 109         validateIndex(imageIndex);
 110         readHeaders();
 111         return infoHeader.getHeight();
 112     }
 113
 114     public Iterator getImageTypes(int imageIndex){
 115         validateIndex(imageIndex);
 116         return null;
 117     }
 118
 119     /**
 120      * Returns the number of images. BMP files can only contain a single one.
 121      */
 122     public int getNumImages(boolean allowSearch){
 123         return 1;
 124     }
 125
 126
 127     // FIXME: Support metadata
 128     public IIOMetadata getImageMetadata(int imageIndex){
 129         validateIndex(imageIndex);
 130         return null;
 131     }
 132
 133     // FIXME: Support metadata
 134     public IIOMetadata getStreamMetadata(){
 135         return null;
 136     }
 137
 138     /**
 139      * Reads the image indexed by imageIndex and returns it as
 140      * a complete BufferedImage, using a supplied ImageReadParam.
 141     */
 142     public BufferedImage read(int imageIndex, ImageReadParam param)
 143         throws IOException, IIOException {
 144         validateIndex(imageIndex);
 145         readHeaders();
 146         return decoder.decode((ImageInputStream)input);
 147     }
 148 }
 149
 150
 151