Index: trunk/src/com/drew/metadata/jpeg/JpegReader.java
===================================================================
--- trunk/src/com/drew/metadata/jpeg/JpegReader.java	(revision 4231)
+++ trunk/src/com/drew/metadata/jpeg/JpegReader.java	(revision 6127)
@@ -1,97 +1,60 @@
 /*
- * This is public domain software - that is, you can do whatever you want
- * with it, and include it software that is licensed under the GNU or the
- * BSD license, or whatever other licence you choose, including proprietary
- * closed source licenses.  I do ask that you leave this header in tact.
+ * Copyright 2002-2012 Drew Noakes
  *
- * If you make modifications to this code that you think would benefit the
- * wider community, please send me a copy and I'll post it on my site.
+ *    Licensed 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
  *
- * If you make use of this code, I'd appreciate hearing about it.
- *   drew@drewnoakes.com
- * Latest version of this software kept at
- *   http://drewnoakes.com/
+ *        http://www.apache.org/licenses/LICENSE-2.0
  *
- * Created by dnoakes on Aug 2, 2003 using IntelliJ IDEA.
+ *    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.
+ *
+ * More information about this project is available at:
+ *
+ *    http://drewnoakes.com/code/exif/
+ *    http://code.google.com/p/metadata-extractor/
  */
 package com.drew.metadata.jpeg;
 
-import com.drew.imaging.jpeg.JpegProcessingException;
-import com.drew.imaging.jpeg.JpegSegmentReader;
+import com.drew.lang.BufferBoundsException;
+import com.drew.lang.BufferReader;
+import com.drew.lang.annotations.NotNull;
 import com.drew.metadata.Metadata;
-import com.drew.metadata.MetadataException;
 import com.drew.metadata.MetadataReader;
 
-import java.io.File;
-import java.io.InputStream;
-
 /**
+ * Decodes Jpeg SOF0 data, populating a <code>Metadata</code> object with tag values in a <code>JpegDirectory</code>.
  *
- * @author Darrell Silver http://www.darrellsilver.com and Drew Noakes
+ * @author Darrell Silver http://www.darrellsilver.com and Drew Noakes http://drewnoakes.com
  */
 public class JpegReader implements MetadataReader
 {
     /**
-     * The SOF0 data segment.
-     */
-    private final byte[] _data;
-
-    /**
-     * Creates a new JpegReader for the specified Jpeg jpegFile.
-     */
-    public JpegReader(File jpegFile) throws JpegProcessingException
-    {
-        this(new JpegSegmentReader(jpegFile).readSegment(JpegSegmentReader.SEGMENT_SOF0));
-    }
-
-    /** Creates a JpegReader for a JPEG stream.
-     *
-     * @param is JPEG stream. Stream will be closed.
-     */
-    public JpegReader(InputStream is) throws JpegProcessingException
-    {
-        this(new JpegSegmentReader(is).readSegment(JpegSegmentReader.SEGMENT_APPD));
-    }
-
-    public JpegReader(byte[] data)
-    {
-        _data = data;
-    }
-
-    /**
-     * Performs the Jpeg data extraction, returning a new instance of <code>Metadata</code>.
-     */
-    public Metadata extract()
-    {
-        return extract(new Metadata());
-    }
-
-    /**
      * Performs the Jpeg data extraction, adding found values to the specified
      * instance of <code>Metadata</code>.
      */
-    public Metadata extract(Metadata metadata)
+    public void extract(@NotNull final BufferReader reader, @NotNull Metadata metadata)
     {
-        if (_data==null) {
-            return metadata;
-        }
-
-        JpegDirectory directory = (JpegDirectory)metadata.getDirectory(JpegDirectory.class);
+        JpegDirectory directory = metadata.getOrCreateDirectory(JpegDirectory.class);
 
         try {
             // data precision
-            int dataPrecision = get16Bits(JpegDirectory.TAG_JPEG_DATA_PRECISION);
+            int dataPrecision = reader.getUInt8(JpegDirectory.TAG_JPEG_DATA_PRECISION);
             directory.setInt(JpegDirectory.TAG_JPEG_DATA_PRECISION, dataPrecision);
 
             // process height
-            int height = get32Bits(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT);
+            int height = reader.getUInt16(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT);
             directory.setInt(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT, height);
 
             // process width
-            int width = get32Bits(JpegDirectory.TAG_JPEG_IMAGE_WIDTH);
+            int width = reader.getUInt16(JpegDirectory.TAG_JPEG_IMAGE_WIDTH);
             directory.setInt(JpegDirectory.TAG_JPEG_IMAGE_WIDTH, width);
 
             // number of components
-            int numberOfComponents = get16Bits(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS);
+            int numberOfComponents = reader.getUInt8(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS);
             directory.setInt(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS, numberOfComponents);
 
@@ -101,46 +64,15 @@
             // 3 - Quantization table number
             int offset = 6;
-            for (int i=0; i<numberOfComponents; i++)
-            {
-                int componentId = get16Bits(offset++);
-                int samplingFactorByte = get16Bits(offset++);
-                int quantizationTableNumber = get16Bits(offset++);
+            for (int i = 0; i < numberOfComponents; i++) {
+                int componentId = reader.getUInt8(offset++);
+                int samplingFactorByte = reader.getUInt8(offset++);
+                int quantizationTableNumber = reader.getUInt8(offset++);
                 JpegComponent component = new JpegComponent(componentId, samplingFactorByte, quantizationTableNumber);
                 directory.setObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_1 + i, component);
             }
 
-        } catch (MetadataException me) {
-            directory.addError("MetadataException: " + me);
+        } catch (BufferBoundsException ex) {
+            directory.addError(ex.getMessage());
         }
-
-        return metadata;
-    }
-
-    /**
-     * Returns an int calculated from two bytes of data at the specified offset (MSB, LSB).
-     * @param offset position within the data buffer to read first byte
-     * @return the 32 bit int value, between 0x0000 and 0xFFFF
-     */
-    private int get32Bits(int offset) throws MetadataException
-    {
-        if (offset+1>=_data.length) {
-            throw new MetadataException("Attempt to read bytes from outside Jpeg segment data buffer");
-        }
-
-        return ((_data[offset] & 255) << 8) | (_data[offset + 1] & 255);
-    }
-
-    /**
-     * Returns an int calculated from one byte of data at the specified offset.
-     * @param offset position within the data buffer to read byte
-     * @return the 16 bit int value, between 0x00 and 0xFF
-     */
-    private int get16Bits(int offset) throws MetadataException
-    {
-        if (offset>=_data.length) {
-            throw new MetadataException("Attempt to read bytes from outside Jpeg segment data buffer");
-        }
-
-        return (_data[offset] & 255);
     }
 }