Document.add(PdfPTable) is very slow in versions 1.3.32 and higher

[zinntech]

Describe the bug
Document.add(PdfPTable) is very slow in versions 1.3.32 and higher
When creating a table with 10,000 rows versions 1.3.32 takes 90,000 ms
In previous versions, this would take less than 200 ms.

To Reproduce
Attached is a simple program to reproduce the issue.
slowPdfTableDemo.zip

To run it:
mvn clean package
cd target
java -jar slowPdfTableDemo-1.0-SNAPSHOT.jar

Expected behavior
In previous versions, this code would run in about 280ms.

Screenshots
None

System (please complete the following information):

• OS: Windows 11
• Used Font: Default

Additional context

[fellmann]

Hi, unfortunately I can confirm this change causes the performance drop. This is because the redistribution of row height is not calculated once per row, but at least x^2. I will try find to a simple fix.

[fellmann]

I will provide a fix today.

[fellmann]

@andreasrosdal This fix should resolve the performance problem.While testing I found another problem concerning missing lines when a row continues after a page wrap. I will create a separate ticket for it, as I believe it is not related this bug.

[andreasrosdal]

Thank you, I have verified that the performance issue is solved now.
Please create a separate ticket for the problem concerning missing lines when a row continues after a page wrap.

[andreasrosdal]

I plan on making a new release of OpenPDF tomorrow with this fix included.

[fellmann]

@andreasrosdal Created #1021

[zinntech]

I just finished testing our product this morning with the 1.3.36 release and it is working great.

I certainly did not expect this issue to be analyzed, fixed and a new version released in less than 24 hours of posting this bug.

Thank you for the fast resolution of this issue, it is much appreciated by me and my team.

[andreasrosdal]

You are welcome. Now I have updated the latest master branch of OpenPDF to require Java 11. This is part of modernizing OpenPDF to work in Java 11+. It would be helpful if you could please test this development branch and see if OpenPDF works correctly in Java 11 for you. Thank you.