Question: Documentation about GreenField- and/vs. PDFBox-implementation

[r-pf]

Dev Effort

1D

Description

Based on e.g. #955, #938 and #939 the following question:

Is there are documentation (present in the web) which describes the reason for a new/second implementation named GreenField and the advantages/disadvantages of it vs. the PDFBox-implementation?

[bdoubrov]

I don't think we put this explicitly to the web site. But the reasons are fairly simple:

• PDFBox is a proven PDF parser, but unfortunately it didn't fit into the PREFORMA project, which required that all the code should be licensed under MPLv2+ and GPLv3+. This excluded Apache license, as used by PDFBox

• the initial version of veraPDF validation was developed based on PDFBox library mainly because it allowed to test the validation model at a much earlier stage. Later on a a completely new (Grenfield) PDF parser was developed

• the goal is always to have both versions of veraPDF to be fully compatible. So, any difference in validation results are to be fixed.

• most of the optimization efforts are spent now on the Greenfield parser. So, we normally recommend this version in long run. But PDFBox version is supported as well.

[bdoubrov]

See also the discussion in #923

[bdoubrov]

The support for PDFBox version will stop after the next release 1.28. It is strongly recommended to switch to the Greenfield version with the continued long-term support