[XGC-7] NullPointerException in TiffImageWriter if JPEG is chosen for compression

• Type: Bug
• Status: Resolved
• Resolution: Fixed
• Affects Version/s: 1.2
• Component/s: image writer
• Environment: Operating System: other; Platform: Other
• Assignee: XML Graphics Project Mailing List
• Reporter: Mark Vollmann
• Created: 30/Jul/07 03:05
• Updated: 24/Jun/15 08:50
• Resolved: 08/Oct/07 08:43

Description

The following snippet does not work because the parameters are not created
correctly.

To be precise:
1. Define imageParameters with "JPEG" set as encoding
2. TiffImageWriter#createTIFFEncodeParams(lines 60++) will NOT call
setJPEGEncodeParam
3. Eventually TiffImageEncoder gets called and in line 467ff a call to
TIFFEncodeParam#getJPEGEncodeParam() is done, which returns null => NPE in line
472 int maxSubH = jep.getHorizontalSubsampling(0);

The whole class TiffImageWriter seems untested because if i look at the source i
see in line 46 the method public void writeImage(RenderedImage image,
OutputStream out) which passes null to as ImageWriterParams to 54:public void
writeImage(RenderedImage image, OutputStream out,ImageWriterParams params)
throws IOException , which in turn passed null to 61: private
TIFFEncodeParam createTIFFEncodeParams(ImageWriterParams params).

First statement in that method is if (params.getCompressionMethod() == null) ,
so you will get NPE here too...

org.apache.xmlgraphics.image.writer.ImageWriter imageWriter = new
TIFFImageWriter();
MultiImageWriter writer = null;
try
{
writer = imageWriter.createMultiImageWriter(stream);
// retrieve writer
if (imageWriter != null)
{
log.info("get image writers parameters");

ImageWriterParams iwp = new ImageWriterParams();
iwp.setCompressionMethod("JPEG");
iwp.setJPEGQuality(compressionQuality, true);
iwp.setResolution(param.getDpi());

log.info("render pages");
for (int pageNumber = fromPageNumber; pageNumber <= toPageNumber; pageNumber++)

{ BufferedImage image; <snip> // do stuff to create image </snip> log.info("write image"); writer.writeImage(image, iwp); }

}
catch...
finally
writer.close()