I have a problem that appears to be one webapp in Tomcat 9 having a portion of its classpath masked by another webapp. I am running Tomcat 9 (versions see below) on macOS 15.4 with Amazon's OpenJDK 11.0.22+7-LTS.
I have 3 webapps all of which use PDFBox 2 and jai-imageio-core (standalone) v1.4.0, largely for converting pages of a PDF to a Java BufferedImage and then to PNG for display in a browser. None of these webapps use com.twelvemonkeys.imageio. Last week I was presented with a PDF with JPEG2000 images on some pages. Having no luck on a command line with PDFBox 2 and jai-imageio-jpeg2000, I tried PDFBox 3. That worked so I updated my most recent app to PDFBox 3 and added jai-imageio-jpeg2000. That worked fine from NetBeans and the Tomcat 9.0.67 dev server. However when I deployed my app to Tomcat 9.0.80 with the other two apps, the JPEG2000 images failed, producing this in my app's log: ERROR PDFStreamEngine.operatorException() - Cannot read JPEG2000 image: Java Advanced Imaging (JAI) Image I/O Tools are not installed org.apache.pdfbox.filter.MissingImageReaderException: Cannot read JPEG2000 image: Java Advanced Imaging (JAI) Image I/O Tools are not installed at org.apache.pdfbox.filter.Filter.findImageReader(Filter.java:171) ~[pdfbox-3.0.4.jar:3.0.4] ... Both jai-imageio-core and jai-imageio-jpeg2000 are in WEB-INF/lib so why wasn't JPEG2000 found? I downloaded Tomcat 9.0.104 and deployed my new app. The JPEG2000 images were fine. I installed one of the older apps via manager, and my new app still worked. I restarted Tomcat and the images failed. Then I copied jai-imageio-jpeg2000 to the old app's WEB-INF/lib, restarted Tomcat, and the JPEG2000 images were again fine. I've since tried this test with both 9.0.80 and 9.0.104 and see the same results. Interestingly, on startup I see the older app's deployment descriptor loads first in catalina.out. I understand the order is non-deterministic, but it appears that if the first webapp with jai-imageio-core does not jai-imageio-jpeg2000 with it, the second app can't find jai-imageio-jpeg2000 in its WEB-INF/lib. I know jai-imageio in webapps is a strange beast, going back to the original Sun versions and Tomcat 4 and 5. When I was running TwelveMonkeys I had a special context listener for that library, but I dropped that library years ago because jai-imageio-core standalone was all I needed. Any thoughts, ideas, or known problems with the combinations I've described above? Any solutions other than copying jai-imageio-jpeg2000 to the other apps' WEB-INF/lib? -- "Hell hath no limits, nor is circumscrib'd In one self-place; but where we are is hell, And where hell is, there must we ever be" --Christopher Marlowe, *Doctor Faustus* (v. 111-13)
